You asked for it :wink.
Improved vehicle simulation - Tracked armor that really rolls and rotates realistically, proper environment interaction (speed/colision), full crews (loader) and detailed and realistic interiors.
Players should not be able to fire top mounted MG's from the interior of the tanks (unless the vehicle features it).
Improved damage model - a vehicle with flat tires can still move and doesnt drive around in circles unless its a tank with a busted track.. better damage system where a player doesnt take damage because someone shot 30 rounds to the vehicles front bumper. Stuff like that.
Improved unit comand interface - They forgot that having multiple weapon mounts per vehicle means we need a way to order a.i. into those vehicle positions (gunner, gunner2, gunner3) aswell, some voices and usefull comands are missing.
Weapons and configs - It took me 3 120MM HE rounds (T72) to destroy one hmmwv. handgun sights are all wrong, recoil is exagerated and strange on the AR's, AK74 sights are too small (actually all the other ones are too big..). Flashbangs and better grenade throwing control. AT4's shouldnt be reloadable, reloading times should difer based on the weapon (belt fed MG's and RPG's should take longer).
Animation - In first person walking feels jerky (more than OPF), the way the weapon sways around should be smoother. I dont understand why i have to stop when i shoot in a mode other than single shot? (even when im dry?), should be able to walk and reload.
Map loading!?! No animated vehicle doors, no fastrope, no walking in moving vehicles... parachuting from helicopters should be gone already, manual fire doesnt make any sense in most cases.
I think Arma could have been even better all around, small things like the vehicles chosen, the setting.. i dont know. Just dont be fooled by the slight negative nature of this post, Armed Assault is the best there is out there and there are many small enhancements that people wont notice at first but it doesnt struck me like OPF did back in 2001, i think it will grow on me though.