I'd like to see introduced a much wider array of damages to gv's, in particular to tanks. Currently, you can only damage the engine and that is all or none; tracks and that too is all or none; turret and that too is all or none.
I'd like to see damages such as jammed turrets (no more traverse), partially damaged engines/drive train (lower max speed), partially damaged tracks (able to move but with major steering correction needed), etc. Also, instead of automatically destroying a tank if the AP round penetrates the armor how about mimicking a crew member getting injured/killed instead and doubling reload times, or decreasing accuracy, or giving it a lower top speed, etc. Just because an AP penetrates the armor does not mean the tank is out of commission.
There are many more things that could be added to the damage model to increase the experience.