The game loop is very addictive and fun. The upgrades were simple, but fairly priced, so that almost each time I could buy something and see the progress. It's great that there are two resources for that (I could imagine this game being more tedious that it has to be if there was only one tied to both shooting at The Big Bad and also buying upgrades).
Graphics were clean, though I think I'd like a hit animation (even those "standard" white/red blinks) when hitting asteroids, because them shrinking down weren't as satisfying given I'm literally shooting lasers at them :)
Here's a few additional nitpicks: distance indicator for mothership is great, but I could really use something similar for enemies as well (maybe the red indicator could change size depending on that, since I was more guarding the mothership than hunting for them - but hey, maybe that was the point and I'm just a dummy :P). The asteroids sprites are nice but them being "spiky" made me think that they will hurt the ship so I was extra careful around them. Then I realised that the gatherer ship cannot be really hurt and it made flying around much faster.
All in all - great game and kudos for the team for creating that in half of the given time!
(Also, I think that the music might've bugged, since it didn't loop throughout the game (and I really liked it!).