Saturn blew up? Sega fanboys are not gonna like this...
The idea is quite cool but the game have some flaws.
Apart from what you said (UI, Start and End screen and a scoring system) the game needs sound fx and some music too.
The camera movement even thought it must had passed from some lerp it becomes the number one problem of the game cause it moves with rotation too and this game requires to rotate too often to hit the asteroids. I think the solution to this is to just use the relative position of the ship and ignore the rotation all together.
Graphics were ok as a tribute to "asteroids".
Physics were rock solid (smells like Rapier).
The idea that the ship is used as a hammer (and it looks like one too) was brilliant.