I tried that tank game... It has some potential... a few things I would work on.
- Make the arrows player controls different (Maybe number pad and 0 to shoot?)
- Fix the animation. don't let it rotate the angle
Biggest thing
- Add some kind of change to bullets... Less bounces (maybe 1 bounce) or so it can only travel so far.
If you don't nerf bullets, you can just spam like crazy and it get's hectic