one thing that annoys me is with the controls.
if you hold RIGHT, then press LEFT at the same time, you'll move left.. that makes enough sense.. but if you then release LEFT (while still holding RIGHT) you don't start moving RIGHT again, you sit there stuck until you release the RIGHT key and press it again
likewise the same situation reversed.
I think your input logic needs to be a bit more intelligent about such situations, obviously if you're playing on a stick / pad it won't happen, but on a keyboard you notice it a lot.
Ideally it should be like this:
if you're holding RIGHT and press LEFT at the same time, you will start moving LEFT, but if you release the LEFT key and are still holding RIGHT you should start moving RIGHT again
and if you're holding LEFT and press RIGHT at the same time, you will start moving RIGHT, but if you release RIGHT while still hodling LEFT you'll start moving LEFT again
try it, you'll see what I mean instantly, right now if feels like the ship gets stuck, you have to release and re-press the direction key.
obviously controls are critical to something like this.