The idea is pretty cool. The balancing is still a bit hard.
A few points I noticed:
It takes a long time until you can build something again.
It would also be cool to show the difference of the different towers a bit better at the beginning.
At the first start I didn't know where the target point of the enemies is and from where the first enemies come. Maybe that could be worked out a bit more.
For a solo project in such a short time, great work.