AS OF NOW

1) Tier 1 is called Collector Rifle X1, Tier 2 is called Collector Rifle X2 and Tier 3 is called Collector Rifle X3.

2) Being the Rifle is a one of a kind and will basically be its OWN WEAPON TYPE, there isnt a need for CV, MG and BM tiers. So as the weapon upgrades, it will still use the same partical effect (as you want) but its stats and abilities will grow.

3) Each tier stays the same in weapon damage as Xcom base CV, MG and BM do... but it has the inate ability to pierce through armor as if it was not there. This is due to its Bio Organic Piercing ammo. Its as if the ammo is ALIVE and can eat through any amount of armor. It has a standard clip of 6 ammo across all tiers.

4) Looking at the Base Assult Rifle for CV, MG and BM... all have added crit damage BUT none of them can crit unless the enemy is FLANKED (yellow icon). Only then will they potentually do crit damage. This Rifle has a added 5% crit chance Flanked OR not. Meaning this rifle can still potentually crit on any hit.

5) The Collector Rifle also has a added built in 5% Aim across all 3 tiers.

6) Tier 1 does NOT have an upgrade slot, Tiers 2 and 3 both have (1) upgade slot for Weapon mods.

7) CAN CHANGE IF WANTED but after testing a bit more, the Faceoff Ability was way too strong on the tier 1 Rifle against early game enemies. As of now, I gave tier 1 (holotargeting), tier 2 has (Holotargeting and Hail of Bullits) and tier 3 has (Holotargeting, Hail of Bullits and Faceoff). You know what faceoff does... it fires the rifle at all targets that are seen which means on a full clip, it could potentually be used to fire at 6 targets. Again, a reason I think it was too OP early on when you are only running into 4 to 6 enemies in a mission lol. Hail of Bullits allows for a GUARANTEED hit at whatever you use the ability on (great for that hard to hit enemy YOU HAVE TO HIT) but the ability consums 3 ammo. So it GUARANTEES a hit but uses half of the clip, provided you have 6 ammo loaded.

8) Decided to not give it the stun or sta on fire abilites as like you said, other weapons (sword) and ammo types already do that.