I came up with an idea during MW3 that was either loved or hated.
LW and Marathon leave a player with less armor since a fast moving player would have less burdening attire.
Blast Shield would have the opposite features. More protect armor leaves a player moving slower.
Scavenger would slow a player down slightly as they would have more ammo equipped
Ghosts (or whatever they call it at the time) would have an equipped scarmabler that keeps them off radar. However, the scrambler blinks making them easier to spot on the battlefield.
SitRep would be a special visor that picks up the signals off electronics. This means the visor would limit visibility.
Ninja or Dead Silence would be similar to LW and Marathon.
I think you get the idea. It has it's downsides as perks would have disadvantages to them but it's more realistic and punishes players in a way that keeps them honest. Campers can use Ghost to sit in obscure corners that make them hard to see physically. Rushers are punished for running around like morons as they need to tread more carefully since they're easier to kill. This idea forces players to play their weakness.