It's one of the best games in the jam!
It's a really well working platformer game + some kind of defence mini-game! For the platforming part - I would touch on the level design, as there is not a quite good distinction sometimes about what is the level's surface, what are "gates" and what is the threat of dangers - for example spikes and slimes decreased my HP sometimes, but there were Saws that were always instantly killing me! For the shooting part - when I got into the rhythm of the enemy ships - the pacing was too slow and I was bored defending it quickly.
But I admire, you managed to create such a game in that short amount of time - there are elements of a complete game and it all together makes an enjoyable title!