This is a good concept: managing your power usage under fire can require some quick clicking
As things are presently, personally I'd say the enemies spawn too infrequently to pose too much of a threat, and moving doesn't seem to benefit you much.
Perhaps if your shields/weapon had a charge level which needed time to recover?
...well take from that what you will ^^;

Funny little game with interesting idea and adequate polishing. Nice job.

Very nice use of the theme! 

I made it beyond 9 minutes before I stop. Very cool idea, but very easy. The right-click quick select made the game extremely easy. Well done :)

Cool game! Cool art, and overall easy to play! I thinks some kind of difficulty progression would be nice, played around 20 minutes and the game felt like it did not get harder to me over time, so it gets a bit boring. Raising the difficulty over time could help this. I also found that I nearly never moved around, and mostly switched between shield and gun. So some kind of reason to use the movement module more would probably a great addition, as it is already implemented ;D But otherwise a nice, chill game!