You just crammed a coconut with too much stuff.
Why do I say you crammed a coconut? this game is metaphorically a coconut, mainly because the basics of this game (bubbles+tanks = game) are small. You then tried to put, in my opinion, too much content into the game. I got bored after getting a level 3 balanced fighter, lost loads of damage over an unseemibly unbeatable enemy and lost a level, giving up after trying to find areas to go back to.
The game map itself needs the map - you dont know where you are in relation to the starting bubble and trying to remember which one youre at only loses your concentration. In the end I lost track of where I was.
All this game involves you to do is to enter a room and kill all in it. Just holding down the mouse button to fire is a pain - easy way to get muscle strain or a selotaped mousebutton, would of been better if there was also a ctrl/shift button to fire aswell. The game would of made this game better with other gameplay - maybe shove in a puzzle or two to break down the action.
It seems youre always limited in movement, since the bubble is such an enclosed area, youre more or less entering and exiting areas. The camera is focused on such a small area that at times I found myself blind-firing to hope if Im hitting the target. The health system is poor, since you dont have one (only losing speed, thats it?) death in the game, even if the ship is really low statistically.
I probably have loads more to say about this game, but im tired and cant think straight. This game should of been much better if it was all-together made to a high standard. Please dont release 3 without seriously thinking of some more useful changes to the game.