The concept is really cool, I've been enjoying so far
It's unfortunate that it's still a bit buggy (game soft locking after a wave randomly), I know you're aware of the bugs though, we shared our struggle on discord haha
Bugs aside, it looks hard also, but balancing is part of the things we would have needed more time for (I know about it, same issue on my game)
It could be really interesting with a few more options like selling items / units, an additional way of earning money
I'd love to play it complete, do you plan on releasing an update by any chance?
Well done!