The game needs to be more informative:
1. would be nice to see more info on the upgrades, because I have no idea how powerful I am getting with each upgrades.
2. Enemy's health should be displayed
3. Have a display for wave count would be nice, so players can be more strategic on the gameplay
There are also some UI that are not polished enough, for example, when I click on a tower that is on the edge of the screen, part of the upgrade UI is out of the viewport.
I might've been a bit too critical on the review, but I would love to see you return to the jam next month, would love to see your progress on the game dev journey.