Icrybecauseimemo made me think of this: How about after every _____ levels, we unlock a hat for each class? First a football helmet for the assualt, and then the tank gets... maybe a gas mask? then the support gets a big italian mustache or a sombrero (See the "PC port confirmed" thread.) then the gunner could get some a tiki mask? then the sniper could get a special helmet, with all sorts of gizmos and sight enhancers. These hats won't do anything, and are optional. They are selected in the "Custom Class" option. Right after choosing a position, if you have a hat, it displays the hat and says "Equip?". If they decide to make a hat every 5 levels or something, allowing for lots of hats, then you choose which hat.
oh ya and we can give the assassin a butterfly knife! and instead of camo, she'll just disguise herself as an enemy player!