First of all, please know that I've decided to just be honest this year 100% so if anything seems mean I really didn't intend that, just trying to be candid :D
Congrats on completing and submitting! That's a huge accomplishment. I see what you were going for here. I really like the visuals & sound, good choices. The controls work but feel a bit too 'tanky' for my liking. That's just a personal preference, though.
As for originality and fitting with the theme.... well, I mean, you know it's an Asteroids clone, basically. Can't give high marks for originality there, and dice don't really have anything to do with what's going on other than just... being the asteroids. The color change is a nice touch, but combined with the tank controls I find it a bit jarring. Two very different movement styles. I honestly didn't try out the different difficulties, but I appreciate it being an option (I usually go for 'easy' these days).
Overall--- I think this is a really solid little game, just not super original and maybe not the best fit for this jam. :)