Boss Ideas

All boss names are absolutely up for feedback and potential changes. Many are placeholders.
Faction bosses:

NCR Lt. Daniel Washer
Uses a highish tier handgun

NCR Lt. Commander Angela Hart
Wears either NCR Combat Ranger Armor, or a variety of LR Riot Gear
Uses an AMR

Legion Verius Aurelius
Chainsaw maybe?

Legion Caesar's Hand
Sneaky, uses a silenced sniper rifle and maybe a katana

(FotA maybe) Hand of the Apocalypse
Heavy explosive weapon, probably a Fat Man

The King
King carbon copy, high health, stylish weapon

Enclave Kill Squad
Marooned somewhere, squad of 3 using varied heavy weapons

Outcast-ed BoS Paladin
Cast out from the brotherhood (maybe for cannibalism, fuck it) and uses high tier energy weapons, likely a gauss rifle.

Creature bosses:

Generally, only creatures which don't have a boss variant (legendary bloatfly,  ghost of she, etc.) will be given boss encounters. Creatures from MoMod lite will be considered, and creatures from the prodlimen pack will be very easy candidates.

Cazaclaw baby pack

Mega-Mantis
Giant giant mantis, in vault 22s big chamber

Mantis ambush
Huge amount of mantises attack you all at once. V22 maybe, elsewhere would be nice

Giant spore plant boss in HH
Will be compatible with spore plant melee attack restored

Giant albino radscorpion boss
In deathclaw territory north of goodsprings

Spectre
Carbon copy of Ranger Ghost, will hunt you down with a copy of La Longue Carabine and an assassin  suit
Might retex the weapon for her to use

Rocketeer
Either space suit or power armor, will use a unique missile launcher with terrible accuracy but really fast reloads
Might use tammers slim version for its model

Hecate and Halsey
Dual boss fought in a locked room
Hecate wears t-51 and uses a minigun, Halsey wears advanced riot armor and uses a red glare.

Coin Counters
Squad all in business wear, using all the varieties of 12 ga shotguns and using coin shot ammo

"Vergil"
Repeat pursuer boss that copies the player's appearance, with different hair color
Will mimic your armor and weapon choice. Offers no loot, but a very substantial xp reward on death. Will find you in interiors.

Might be given a ghoul default appearance and have un-breakable limbs as a default, with the player appearance and equipment mimicry being optional
Might have a Benny appearance option too.
Intended to hound you primarily in the early game, from about the Mojave outpost onwards.

Alien Ancestors
Egyptian god themed aliens using the ancestor armors