Quite cool! Reminds me of the game COLOSSATRON by Halfbrick - with some important differences! I'm not sure whether there was a win condition, but if you were to work on this game post-jam, I believe it could be turned into a really good arcade game. For example - the win condition could be similar to what COLOSSATRON does, namely, you have to destroy a certain amount of landmass (in your game, that could be the little drones that attack you) in order to proceed, so that you can buy upgrades, etc.
Definitely a high Creativity and Enjoyability score from me! I'd really like to see where this goes with some more work. (4 days is not a lot of time - and I think we gamedevs all know that, haha 😅)
EDIT: Just noticed this has only 6 ratings. Definitely needs some more! 💖