The game has been updated. The destructo beam did not seem to be working, so I was able to resolve that. However, it made me realize that the destructo beam was not available until a very late stage, because otherwise players would have noticed. I have moved up the upgrades in general, so you should be able to find more unique upgrades earlier in the game.
The Destructo Beam in Action
Faster Shooting
Also, I sped up the rocket's shooting ability. Now you can shoot about three times faster (three times more fun?) but be careful, you will still lose points for wasting bullets!