@Kevin777. I was totally thinking the same thing about an anime being made based on this game. Its rare for me to enjoy a storyline to the extent that I'm compelled to keep playing just to enjoy the story.
@mtn silviu. The cost of upgrade is not a bug. There's even an in game tip that suggest to hold out for higher upgrades to save more money in the long run. This was set up that way on purpouse.
They don't just shoot upward spiffydruid. You can switch direction by pressing v. I don't bother with switching directions but just make sure to have my ship tilted so that the cannons shoot in the direction I want it to when my ship is vertical.