Well, not too much improvements needed
but it's just not fun at all. A few ideas that might make a little better:
- Difficulty settings (more money per shape, but more health) or (newer enemies quicker).
- More shapes (octagon, oval, rectangle, 6 sided star, etc.).
- Bigger playing area.
- Boss every 30 seconds or something.
- Maybe more background music loops.
- Fix the auto-heal upgrade?
- Interest rate for every ten seconds.
- More upgrades such as: Auto-bots ($200, but slow), Increase interest rate ($25, but increases difficulty) or amount of money received from shapes, Armor for base