Just posting everything I thought of...the only thing I suggest is the addition of nifty features.
-Keep the "official glitches", make no changes
-New bounty stuff
-Dispose of Premium Medical Items
-Moar crosshairs (dot must be there)
-Obviously no lag
-New character animations for the button presses (Taunts, casual actions)
-Premium Headgear doesn't change hairstyles
-New ideas for character appearances
- Day and night stages for each map (The night snow Town stage was epic)
Now THIS one may be asking way too much...
- Let the characters from the GunZ artwork be featured as final quest bosses, training dummies, (or something) They would move in the same pattern as a normal person would, K-styling and the like. (That's the incredibly hard part, this might be nvm material.)