Not sure if it is good but here we go.
How about attachment pros
Such as...
Red dot = Maybe like the BO series and have it coloured and styled up
Thermal = Detect explosives
Extennded mags = Even more ammo
Tac knife = You can run into players with a tac knife to kill them instantly, because that does bug me when you run into someone with a tac knife when in reality it would moe them down.
Silencer = Let alone being invisible on the map but you can't be heard from players close by so it is actually silenced.
Just a few ideas I had in mind, what do you think of it. I doubt it will happen though because I think Treyarch hinted in Black Ops 2 that there will be no more Pro's on perks. But that is Theyarch and this is Infinity Ward.
So what are your thoughts?