Imagine what the game would be like if you could hold triangle / y button / etc. and do various actions like pick up any dropped weaponry instead of a whole class, and/or other actions with gun features.
Also, players may be more inclined to buy maps or even go premium, if they are aloud to access new weapons, maybe not immediately like premium players, but a short time afterwards.
(Not sure if this has already happened, I have premium)
Combos with melee weapons wouldn't be such a bad idea, sure you'll kill faster, but I'm sure it'll make this game a chunk more exciting.