I felt that this was a well done game, music might at some points been a bit loud. Otherwise a new take on the classics and adding those shop items was creating some reason why I would keep shooting the enemies. I think this with some polish and different kind of powerUps, or even that you could add some extra things on the ship (which could be automatic, like a turret or something) could spruce it up!
Took me a while to understand how I get points, since I was just destroying everyone with the other ship, which just works as a collector/shield, but once I got it, it was relatively understanable and good idea.
Small annoying thing I found (which might be intentional), was the ship is not shooting if you're not moving. I kind of understand that, so you can't just shoot and cover with the other ship everything that gets too close, but somehow it felt a bit off can't put a finger on it that why it did, since I understand the reasoning for it in that sense.
The start screen I thought as someone had mentioned here that I could control with either wsad or the UDLR keys, but they controlled different things, but that only took like 5sec for it to sink in when I started playing.
At first I didn't really see (too small on my screen) which button I should press to open to shop and once I got in, I wasn't really sure what button to press to get out, but the same was for both. But I think the reason I couldn't really see the e that it says there was, because Itch.io would let me go fullscreen, well it did for the main part, but your game was still a small area only that showed.
But overall I would say it's a great game and I spent more time on it than I originally thought! Which when playing SO many games during the game jam, can sometimes be a bit hard to do :D