I read through this entire thread and got some great laughs over the fanboy fights over balancing the game.
Realistic rather than balanced? Now way! I'd much rather have a marine choke-hold an Alien if it adds balance to the game.
Personally I like all 3 races (Aliens and Marines more), so I'd like to have a fighting chance with ANY of them.
And honestly, we are talking about freaking Aliens and Predators here. Nothing realistic about them in the first place.
I just hope the Predator is not TOO powerful. (cloaking, laser-targeting insta-kill, melee, and ranged attacks)