I don’t think balancing has to always include nerfs.
Picture this: Predator drops down and starts attacking a teammate. I walk over and start unloading into the Pred with the mini-gun. Predator kills my teammate, runs over to me, and kills me in a few slashes. I’ve just unloaded an ENTIRE CLIP from the mini-gun into the Pred. The FT’s guns have been nerfed so much, I might as well be using harsh language.
What if instead of nerfing FT’s guns to the extent that they actually are nerf guns, you buffed the NPCs against the FT to create opportunities for the Pred. I think the FT need more DISTRACTIONS to pull their attention away from the Pred, thus creating openings/opportunities for the Pred to come in and get some kills. If the NPCs were significantly stronger against the FT, the FT would have to pay closer attention to them, and would also take more damage from them, making it easier for the Pred to clean up.
In short, I enjoy your game, just maybe slow down with the nerfs and find more interesting ways to balance FT and Pred.