Hi! I really like the game.
I've played a bit of both survival and local multiplayer. Both modes are fast paced and the controls feels very fluid and intuitive. However, when playing local multiplayer me and my friends agree that using the keyboard/mouse controls feels easier and almost advantageous compared to the controller. It is not a big deal. Maybe we all just suck at using the controller.
As for powerups, i think that you should definitely add them. It adds variety to the game so that players can perhaps choose a new strategy paired with a powerup every game time. I think a speed/control powerup would be neat which increases speed yet decreases drift to make your ship super maneuverable.
Anyway, excellent game! I look forward to seeing how it improves and changes over time.
P.S. Is there an easier way to update to newer versions than downloading the file from here each time?