Some issues
Its good but some major issues that prevents it to be awesome.
--Major slowdowns that affect the controls a lot:
slowdowns are not necesarly bad in these kinda games if they dont affect the controls but here the ship keeps moving after you stop pressing the move key and it gets you killed.
--You can destroy your own missiles: So you can't use your missiles with your other weapons and you have to actually stop shooting when you use your missiles against a single enemy.
--The levels are a little repetitive: You should introduce more new enemies per level, for example the first level is too boring.
I like this kind of space shooter games, so I kinda like it despite the issues, so good job and I hope the feedback helps you.