Tactical nuclear devices and friendly fire.
Tac nukes and friendly fire will bring forth a depth and realism to this game that has never been experienced before. Instead of you and 3 friends mobbing up on the same enemy, smacking each other wanton with your weapons, wouldn't it be cool if you took damage from your allies attacks? And when you get a 50 killstreak without getting damaged, how about you get a tac nuke that clears the level?!?!?! Of course it'd kill you and your teammates, but that's fine. use 5 E to revive! duh!
Games in the past have strongly benefitted from friendly fire and even from tac nukes! I mean look at call of duty. THEIR Combination of extreme connection issues (Which we already have now, so thats one step to success already taken!) and tac nukes plus friendly fire made their game sell millions of copies.
I say to OOO that if they really want to make this game great, push out a whole bunch of overpowered and ultra exclusive microtransaction content, give us friendly fire and tac nukes, and keep this terrible server connection issue. It'd make the game so fun, we'd run WoW into the dirt.
EDIT: I'm serious.
This isn't Modern Warfare and friendly fire would get people killed even faster than they already are. They put that one in and I'm stepping.