Thanks for the time you spent on it!
To answer your suggestions:
Pacing - yep, that is thing i currently consider very heavily to make the action faster.
Laser fire rate - there are permanent upgrades for it and there is also a powerup that increases fire rate. In the future i also plan more main weapon types, one of which will definitely be faster shooting with lower energy consumption and damage :)
Enemy variety - not sure how far you got, but more enemy types are appearing once you defeat few bosses...to ease the player into it a little bit. But yes, more are definitely coming, and bosses aswell.
Once again thanks for feedback!