I enjoyed this one a lot. I thought the top-down asteroid-like movement was well implemented. You might look at smoothing the hitbox of the ship a bit more to make collisions with the space objects a little easier to get out of. I thought the vide was well done, and you did a good job of centering on a couple key mechanics.
I think my main feedback is there is a lot of talking/reading. Especially when explaining the missions - the timer should probably stop when the mission text is going (so your players can appreciate the jokes you put in)