My only solution (and one that I personally think is really the only valid one) is to keep the knife as a tactical addition to the pistol or make it a separate weapon completely. Let people get 1 hit knife kills, but if isn't a tactical knife then the user has a delay in which they can use their primary weapon again (basically a "you pulled out your knife so you took your hands off your gun kind of thing.)
The problem with a knife being several hits is that, the knife as a viable weapon would drop very quickly because most people would get stabbed once, turn, and blow you away. Secondly, you're supposed to be a trained solider and there are way too many parts of the human body that would require only a single hit to take you down (maybe not an instant kill, but you'd be in no position to fight back); that any more hits and you'd be a pretty fail soldier.
I'm a bit on the fence about the lunge, it has good and bad points, sure it sucks that someone can fly through bullets at you and knife you, but go load up something like MW1 and play with the no lunge/tiny lunge. People whiff the air a ton in that game, the lunge somewhat helps with what should be a pretty easy hit in real life. It ends up being a necessary evil, imo.
The problem with a knife being several hits is that, the knife as a viable weapon would drop very quickly because most people would get stabbed once, turn, and blow you away. Secondly, you're supposed to be a trained solider and there are way too many parts of the human body that would require only a single hit to take you down (maybe not an instant kill, but you'd be in no position to fight back); that any more hits and you'd be a pretty fail soldier.
I'm a bit on the fence about the lunge, it has good and bad points, sure it sucks that someone can fly through bullets at you and knife you, but go load up something like MW1 and play with the no lunge/tiny lunge. People whiff the air a ton in that game, the lunge somewhat helps with what should be a pretty easy hit in real life. It ends up being a necessary evil, imo.