Very nice movement mechanics! Very good looking game!
Only problem is that the best strategy is not to use any of your movement mechanics. Using the doors is extremely risky and almost always leads to death and the jump, shoot down combo is tricky to perform. Best strategy is to keep standing on the top platform and hitting the fire button. There is no reason to move.
I think a clever way to fix a lot of these problems would be to change the shot so it ALWAYS fires downwards. Makes the jump shoot combo easier to perform and doesn't allow you to stand still quite as much.
Maybe get rid of the doors. When you can teleport, that makes one of your most interesting mechanics a little obsolete, doesn't it...
Great game! Would be interested to see this with a couple of minor changes.