Of all the jam games, this one screams "make me a product" the most! The completeness of the design and implementation are awesome!
You already know about the balance issues. And there's need for some tutorial, obviously. I guess what other cool things could you add? Going down to the planet for a little R&R/adventure? No? How 'bout make it multi-player and let one person move the ship while another attends to the turrets and weapons. Heck, another person could run around doing repairs real time.
There's so much you could do! I hope you decide to keep going!
I'd sure like to know what ace developers such as yourself think about my game! Please give it a try and let me know what you think in the comments. Thanks!