This is really fleshed out for a first game--nice job on that! The enemy movement is pretty complex as well.
The tutorial felt a bit overwhelming at first -- I would have preferred if there was a way to introduce things to the player in stages as they play with a guided tutorial level or something.
It's also pretty easy to accidently click through the tutorial with left/right click and scroll wheel -- I think individual buttons to proceed/go back might have been better.
Gameplay-wise, I felt like the combat was a bit restrained due to not being able to fly to the edge of the screen, and not being able to shoot backwards (while your enemies can do both.)
Impressive work, looking forward to see what you do next.
-Bacon