Along with selecting between weapons, we should be able to decide between:

2-3 grenades OR 1 shot disposable RPG(you can't get more ammo without dieing)

^Don't even say "rpg omg omg mw2 mw2 shit shit" the projectile could be similar to this, ofcourse with the power of a grenade http://www.youtube.com/watch?v=y34o-MMQUu4&feature=related

heavy armor(-30 percent speed 50% HP) OR none (+20% speed) OR Less equipment (+40% speed, -30% HP)

Extra ammo (-10%speed +50% ammo) OR Normal ( no difference )

Lol^ if you choose heavy armor, and extra ammo, you better be defending!

Side arm OR kukri?

Or maybe you could even have marathon pro <- joke but everything else is serious.

a minor suggestion, just popped into my head whilst playing an epic grenade fight with a squad of enemies.... as in rockets flying over head or hitting my cover :3