New features

After releasing this game successfully, I can start developing some new features. I've many ideas to improve the game:

• Collectable power ups
  • Sometimes a power up appears. The player must collect it, by hitting it with his figures:
    • Power shot (Higher velocity)
    • Freeze a figure (own or opponent)
    • Iron ball (Ball is heavy, will move slower, but has higher mass)
    • Respawn a disqualified own figure
    • Ghost (Can shoot through figure)
• Tutorial
  
  • On first start, own figures and goal are highlighted
  • Hint, that you need to use the mouse to set direction and velocity
• Better sounds
• Gamepad support

These are my current feature ideas. What do you think about them? Any other ideas?