Outstanding work on the look and feel of this game. It falls a bit short on the handling side however. The tanks feel a bit too much like they're slipping around instead of grabbing the ground. Due to the nature of the game, it's in a weird spot right now where it's not a "fast action" game, but it's also not a "slow strategic shots" game. For some ideas that could fix this, consider letting the player fire with the mouse, having the turret head aim where the mouse is, independent of the direction they are traveling. Also try to give the tanks more of a "momentum" behind their movements.
This is a great framework, at this point it just needs a few tweaks. Excellent entry!