The game has quite a pacing problem. There are situations in which the pressure is really up (like, instantly), and then there are situations in which you are really just waiting for the game to "continue", as a player (at least for me, let's put it that way :-) -- my point is, the pace is either 1 or 0, there seems to be nothing in-between.
Also, readability is a major issue. Some ships seem to damage me, others don't seem to do it -- overall, the game is pretty, but it's hard to understand what's actually happening on the screen.
Hope this feedback helps! :-)