I think the following functions with weapons need to be kept in mind with Nexuiz, especially with the addition of vehicles.
-Melee weapon for close range attack
-EMP weapon to disable vehicles and also cause rockets to exploded in mid air

which would be very fun agents rocket monkeys
-repair weapon to repair damaged vehicles and nodes in onslaught matches
-a shield weapon, say which only protects agents energy weapons, very useful agents nex camping consumes health or energy
-a secodary weapon to the shotgun, possible some sort of blunderbuss gun which is effective agents air vehicles
-of course there can be many other damage based weapons but i think those functional weapons will needed!
If you were able to convert one of there functions into a melee weapon it would be great. i personally think the EMP function would be fantastic 