I also added the turtle enemy. It is very slow and big, and takes 10 hits to kill. Considering you can do rapid-fire, that isn't really hard. They are worth a lot of coins though.
I also py2-exe built the program so people can test it. This usually takes a long time, but in last years contest, I found a tool called pygame2exe that did some of the dirty work if you had configured it properly. The compiled files are here, (just extract and run main.exe) If a few people could try it and comment on the music, the FPS, and anything else it would be nice.
I tried out the game and it ran great. No FPS issues. The music is in the decent-good range. The sound effects are decent, but they were a little on the loud side. Controls are responsive and smooth. Graphics are good. Instead of calling it a turtle enemy, call it a carrier sphere since it looks like it launches fighters.
I don't understand how "Death is Useful", in fact it seems to give you a penalty for your final score. Your biggest point gains for your final score will probably be found here since Theme is worth 20 points.
Bugs:
Hitting the left arrow turns the ship right while hitting the right arrow turns the ship left.
(minor) - Clicking on the name to enter your high score just continues on.
(cosmetic) - Countdown displays single digits 0:7 instead of 0:07.
All in all, a nice, clean entry.