I had fun playing this game.
I invested in factories early on which means I got a lot of money in the end. The issue is at wave 6 and everything after the game was lagging so hard I could barely add anything anymore. not sure if this was an issue on my end or the game itself tbh but it happened two times starting wave 6.
I made it to wave 9 but at that point, the game wasn't responsive.
I suggest some balance where killing enemies gives you more coins. Even though investing in factories early on grants you a lot of coins at the end game but killing enemies should be more rewarding.
Also, I used the walls to shut off my base completely and I think this broke the Ai bc they were standing still and not moving anymore.
I think the game has a lot of potential. Good work!