Hey neat! This is a neat game, I'm honestly hard pressed to find faults. Someone says below that it's unbalanced, but I think you've done brilliantly on the balance. It seems like you get the same amount of coins each run, and part of the fun was having a crazy number of turrets. Even at the end I had enemies coming close to the exit, so the difficulty felt just right.
My one criticism is that the game's 'gimmick' didn't feel fleshed out. Without control over the turrets, there wasn't really much to do other than shoot and go for coins, which is fine, but the game ended up feeling a bit hollow. It'd be more interesting if the player had some agency, perhaps you could pay more to get a better (but still random) turret? Or maybe you let the player move turrets, so the turret type and initial position is random, but the player could then optimise the positioning?
It's still a very solid game, and the graphics are great as ever. And just as a side note, your game page is looking slick!