Alright, so after playing around with the latest version a bit, there's only a couple things I would consider changing.
1). The Imps' capacity for projectile saturation is still too high imo. The only nerf I'd suggest is bringing their fireball multishot down to 2 max - I think that would go a LONG way in making them less oppressive.
2). Overall, I like how the Cacodemons feel like a major threat and not just a flying bullet sponge.I'm also a big fan of how their dashes cancel their recoil - so there's fewer Cacodemons flying off to a different postal code. However, I think their spread shot is a bit too much. On certain maps it becomes nearly undodgeable.
If I could give a couple suggestions, maybe you could replace it with a shotgun spread of projectiles that has a vertical spread - play into how it's often hovering above you. Or maybe a projectile that increases in size with travel time - taking advantage of the fights with Cacodemons at longer ranges. Or maybe give them a railgun-type the player can narrowly dodge. That keeps them threatening at every range. I saw something like that from the Arachnotrons in Strange Aeons.
3). The current Rocket Launcher feels like it might be a little *too* good. But rather than dialing back the damage, it could be an interesting spin on the weapon to make it a bit slower between shots. Give it a reload that dials back the dps that way...
4). As good as the Chaingun feels, I think that its fire rate is too high. It often breaks encounters with how quickly you can mow down a target. It may burn ammo fast, but that's not terribly relevant if a level that gives you bullets and expects the challenge to be the time spent focusing down targets.
Aside from that, everything's flawless to me. I love this mod a *lot*.