Starting worst to best. Boss fights are not taken into consideration.
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Time-stopper;

Crash man: 9/10
Spamming it causes you to lose no ammo while it slows down enemies, a trick to utilize. Can spam it to bypass any enemies quite easily, though you have to be strategic with your uses since it slows you down on ladders. Doesn't help for the giant met, and doesn't stop the arrow platforms for [reasons]. Recommended doing full stops for the met dropping, pipi and flyboy sections.

Wood man: 8/10
The beginning section with the robbits can be somewhat hard if you try and spam them and jump over, though you can also pause them midair and go under (you may want to save ammo for the hotdogs though). The infamous glitch of skipping past the hotdogs while the weapon is activated from off-screen is still in effect, and after that you can save the rest of your ammo by spamming again.

Quick man: 8/10
Not very useful for the changkey makers since they're too large to properly jump over (though the first is easier), otherwise spamming makes the force beam sections a joke.

Air man 9/10
Can do a full stop to skip past the tikis as they're spawning in to avoid the horns, as well as spamming to stop fan fiends from slowing you and being able to run under pipis.

Bubble man: 6/10
Doesn't do much for you. Can spam the falling blocks, hermit crabs, and jellyfish enemies. The only thing that's notable is letting you run through the falling crab section. The frogs and lantern fish get in the way, though suppose you could use it to get up close to the frogs in the beginning then attack.

Heat man: 10/10
Can spam the first two screens of flyboys and jump over them, and on the third spam and run under when they begin to rise (also for the flyboy before the end). Afterwards, you can spam your way past all the other tellys and stop the springers. Can also use it to impede tellys during the yoku block section. Doesn't effect the yoku blocks :(

Metal man: 9/10
Going under the presses, just activate it for a quick moment before deactivating to save ammo. Works well for most challenges, including spamming by the mole section, though there's a few enemies that get in your way you'll have to kill.

Score: 59/70

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Leaf shield;

Quick man: 8/10
Doesn't work on springers :( Only kill two of the four changkey makers in the first section (preferably the latter two), then grab the first two ammo pickups in the force beam section and you can kill the last two at the end.

Air man: 10/10
While not particularly useful during the first section, it still works fine and can kill any enemy with ease. It even has an ammo refill after the air chariots if you need. Afterwards, as the enemies stack up a bit more, it becomes more useful for killing all of them, and can even use the pipis and scworms to farm. Good to throw at fan fiends. Doesn't dink off the tiki horns which is helpful.

Bubble man: 10/10
The frogs take three shots each which may take a while if you want to farm the mini frogs each time, though you can use the shield to get up close to them before shooting. The lantern fish also take three shots, and you can also farm the shrimp they produce too. Everywhere else has weak enemies the shield is great for, including the crabs and jellyfish. The shield works great if you just have a little patience.

Heat man: 9/10
Still doesn't work on springers. Flyboys take two hits, but you can farm in the first telly screen right after. Afterwards, you can easily run through the rest of the stage.

Metal man: 7/10
Mostly useless on all enemies, given that pierrobot's wheels take three hits and the other two enemies are immune. Moles are the only thing it's really good at, making the one section a breeze. If you want, you can ignore the first pierrobot and take out the next two, and you'll have one use left where you can farm in the mole room, and afterwards should have enough ammo for the last two pierrobots.

Flash man: 8/10
Very good on the shotmen, killing them instantly and blocking their bullets. You can run through the entire beginning section easily (can also throw the shield up for that last screen of the section to save a use). Blockys can get in the way, but they're not much of a threat. Can grab the large ammo from the alternate route without needing to take it, but farming scworms is also available, though not needed since sniper armors are also immune to the shield and it's best used after for the last shotman at the end.

Crash man: 9/10
Tears apart pretty much any section, mainly being made of tellys and mets. The flyboys aren't much of a problem if you play a little more offensively. Can farm on the tellys and pipis. Not recommended on the giant met.

Score: 61/70

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Air shooter;

Bubble man: 8/10
Good on the frogs since aiming it out can kill their babies, then using it up close should finish them off. Otherwise the stage is filled with weak enemies that are easy targets (hermits crabs are best dealt with up-close to avoid their shells). Not very good on the lantern fish though, they take four full shots and trying to stay close without getting hit can be hard.

Heat man: 10/10
One-shots both flyboys and tellys, and them being aerial only makes it even better, thoroughly outshining the small setback of being immune to springers.

Metal man: 9/10
A full shot can entirely take out a pierrobot, and two pieces can kill a mole, which with some positioning can be quite useful in that section. Blockys and springers are immune, not too bad though.

Flash man: 9/10
Some shotmen are out of range, and others are positioned well for it, which can be very useful when paired with the buster. Very good against scworms, and one whole shot can kill a sniper armor while blockys and springers are immune.

Crash man: 10/10
Tellys, pipis and flyboys all become easy targets that're instantly killed. Good on the first two mets, and can take out the large met with four shots. Ammo pickups along the way are also helpful.

Wood man: 8/10
Robbits will need at least two shots to kill, and hotdogs take five full shots. Recommended you kill the beginning robbits then save for the ammo pickup after. Works very well against pipis with its range, and very decent for monkings and kukus too (both take two pieces). One-shots battons.

Quick man: 9/10
While it doesn't work on springers, two pieces of air can kill a changkey maker, meaning you can take them all out easily with a single shot.

Score: 63/70

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Bubble lead;

Heat man: 9/10
Not very good on the flyboys, but works well for tellys and can kill springers.

Metal man: 10/10
Kills the springers, and good for pierrobots. One-shots moles, and if done right can run through the entire mole section without stopping. Blockys can be somewhat hard to hit, but it's doable up-close.

Flash man: 8/10
Kills shotmen in two shots, though positioning varies. Good for scworms and springers, otherwise it's not the best.

Crash man: 9/10
Does its job at killing tellys, a few beginning mets, and the mini pipis. Not very good against the large met or flyboys.

Wood man: 9/10
Kills robbits and kukus in two hits and hotdogs in five. Tears through mini pipis. Battons are immune, but they don't really get in the way. Monkings aren't weak and not being able to hit them from below can make them somewhat pesky.

Quick man: 10/10
Good for killing the only two enemies that appear- springers and changkey makers. No comment.

Air man: 8/10
Can be used to hit the goblins spawned from below you on air tikis, and tears through mini pipis. Not very good for the air chariots, and is weak against fan fiends and lightning lords, as well as having limited range on them.

Score: 63/70

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Metal blade;

Flash man: 9/10
Being able to aim makes most of the shotmen quite easy, and it handles scworms well. Sniper armor and springers can get in the way. Blockys can be hit, but it's a bit precise.

Crash man: 9/10
Works fine on the tellys and starting mets, as well as being relatively helpful on pipis, though otherwise doesn't do much special. Has an advtange on the large met, being able to aim lets you get a few more hits in than regular.

Wood man: 9/10
Positioning for the later robbits, battons, and monkings all work great paired with the aimability, and frequent ammo. Otherwise average in the beginning, though you'll use a fair ton of ammo. Not recommended against the first two hotdogs since it's rather weak still, but the aiming still does have an effect, and it can even hit the third hotdog without leaving the safe zone. Doesn't work on kukus.

Quick man: 8/10
Somewhat moderate on changkey makers, though springers are immune. Last one can be harder to take out with the springer.

Air man: 9/10
Can be helpful against the pipis and to be aimed on a couple of fan fiends. Otherwise it works very well as an above-average buster replacement. Also fine for air chariot sections.

Bubble man: 10/10
While not having a lot of power, the penetrating effect definitely helps against both the frogs and lantern fish, where timing your shots right can easily kill the enemies they spawn while still hurting them. Otherwise works well on all other enemies, and aiming can help for the last few crabs at the end.

Heat man: 9/10
Very good for taking out tellys, more moderate for flyboys. Aimability compliments both well. Springers exist. Can also trickshot the tellys by deflecting the blades off the destructible walls.

Score: 63/70

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Crash bomber;

Wood man: 9/10
Many good places to use it. You can kill the four robbits that get in your way at the beginning then use the remaining three shots on the hotdogs and grab the ammo drop after. You can potentially try and kill all the mini pipis at once in an attempt to farm, but it's not consistent. Instantly kills the monkings and kukus. There're two small ammo drops near a robbit, just enough for a single shot to kill them no matter you're current ammo. Space out shots where you find areas to be the most hard.

Quick man: 9/10
Can very easily kill every changkey maker, too bad it doesn't work on springers.

Air man: 10/10
Using it in the air chariot section is pretty pointless, as well as against the single wall, but that's about the worst of it (also instantly kills lightning lords). Using it on the air tikis where the goblins may get you (past the first one) and on every enemy that gets in your way will carry you through the entire stage, and that's excluding potential ammo drops when used on the swarm of mini pipis. You'll likely have excess ammo, so use it freely.

Bubble man: 8/10
Can destroy the five frogs and two lantern fish that get in your way, taking out all of its ammo. Every other section with weak enemies recommended to be done with another weapon to conserve ammo, though it still works very well throughout the entire stage regardless.

Heat man: 10/10
Efficient in killing the flyboys and tellys in the beginning, though if you want to destroy all the walls only use it four times in the beginning section. Afterwards, you can destroy the first wall and grab the ammo in the first yoku screen and explode every wall that comes after. Grab the ammo pickup at the end and you'll have enough for the last two walls. If you use it five times in the beginning, you'll have 2/4 ammo needed for the last wall of the yoku section, though you can also quickly farm the tellys on-screen.

Metal man: 9/10
Killing every enemy in the way (not including springers), you have just enough ammo to make it to the end and take out every enemy. Inbetween, you'll have one free shot you can use on the moles, which can also be helpful with the manual explosion in the air.

Flash man: 9/10
Kills any enemy in a single shot that isn't a springer. While it may not be very helpful in the beginning, once dropping down from there it can be used to kill any select enemy that gets in your way. It's better used for the two walls below, one letting you entirely skip over the armor joes. Enemies don't get in your way much, so using it somewhat sparingly can take you far.

Score: 64/70

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Quick boomerang

Air man: 9/10
Effective, but overall kind of average. The limited range can be a bit of a setback at times but it also quickly kills any enemy. Can use the rapid fire for fun in the air chariot section.

Bubble man: 10/10
Tears apart enemies, and is extra effective against the frogs since it can also kill their babies. Some of the smaller enemies require a little bit of good positioning, but is overall very effective. The hermit crabs can be a bit awkward to dodge.

Heat man: 9/10
Despite them not being weak, it allows you to basically run through the entire beginning section with the flyboys and tellys without needing to stop. Otherwise it's fairly standard. Doesn't work on springers :(

Metal man: 8/10
Still doesn't work on springers. While they're not weak, it can still quickly dispatch a pierrobot if you don't run up on them. Moles and blockys are both weak, and it's fairly good to use on both too, the former being a bit hard but rewarding if skilled enough.

Flash man: 9/10
There're a few shotmen that just out-range it, though otherwise it works perfectly fine for every other enemy (including sniper armor). Shotmen are weak to it, and the last four of the beginning section are pretty easy targets.

Crash man: 9/10
The arc is rather convenient for hitting the tellys and pipis, as well as letting you just run right up to the beginning mets. Also takes out the large met fairly quickly. Not good for the ending flyboys.

Wood man: 10/10
As expected, it tears through enemies still. The arc is convenient, being able to hit hotdogs from the ground, monkings from below, and that final robbit from below. Also good on kukus.

Score: 64/70

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Atomic fire;

Metal man: 10/10
Besides springers, it can kill every enemy being held out and fully charged instantly and only use 1 ammo per enemy. Being able to hold it lets you basically run through the entire mole section without the need to stop. Blockys are a bit hard to hit with it.

Flash man: 9/10
Still kills every enemy when fully charged, apart from the springers. Even though some shotmen may be out of range while holding, you can fire 2 small shots at them to kill them.

Crash man: 10/10
Continues to kill every enemy while held and fully charged. Somewhat inconvenient having to constantly swap weapons to save ammo when climbing up ladders, but it's fine. Works well on pretty much every enemy, though shoot a semi-charged shot at the mini pipis to save ammo. The large met does take three fully charged hits, and the first 2 will take away your ammo as if you had shot it out, but there's an energy pickup soon after.

Wood man: 10/10
Guess what... it kills literally every enemy while being held out in one shot, even the hotdogs. Still advised you shoot it out against the mini pipis.

Quick man: 9/10
Kills changkey makers with a fully charged shot, though doesn't work on springers.

Air man: 10/10
Makes for a great guard while on the air tikis as well as killing scworms, and that's most of the melee aspects of it. Can also kill the pipi egg before it hatches, though if you still want drops then shoot it at the mini pipis. It's mostly an ammo waste for air chariots, though you can shoot three uncharged shots at fan fiends to kill them.

Bubble man: 10/10
With the abundance of enemies, try and not go out of your way to hit too many to save ammo. You still have a lot ammo, so there's not much to worry about. Oh yeah. Fully charged kills everything in a single hit.

Score: 68/70