Awesome mod, though I do have some suggestions and issues to point out:
-The kick doesn't seem to benefit from berserk, nor does it "autofire" like the fist's primary attack.
-The kick impact becomes a chaingun firing sound if you kick with the chaingun equipped.
-The Lost Soul fatality is very easy to hurt oneself with, especially if there's a lot of them around. Hilarious, though!
-Having the Pain Elemental do splash damage on death seems unnecessary, given the Lost Soul's increased aggression at close range (or did you not do that?).
-Bullet boxes don't seem to add to my ammo...
-Chaingun guy's fatality should have him shout when you deliver the finishing blow...
-BFG shouldn't have splash damage, at least not to the player, IMO.
-Berserk "right hook" feels awkward to use, since it's so slow to come out. Perhaps more of the delay should be after the punch?
-The extra smoke and flames can make it difficult to actually see what's going on in a heated firefight.
-Sometimes monsters seem to take damage and die from the different gore effects... is that what's going on?
-Some of the monsters can hurt themselves, now that most ranged attacks have splash damage.
-The constant liquid "slosh" when actors are moving about in water/nukage/whatever gets VERY annoying.
-Monster infighting is AWESOME now!!
-If you have Berserk, you should be able to skip straight to the fists instead of waiting for the chainsaw's ready animation to finish.
Can't wait to see what's next!