Hey! Just gave your game a try.
Off the bat, I had a hard time understanding what to do, but not because I was unfamiliar with the mechanics. It's hard to tell the blue and green apart in the UI, so I couldn't tell that some of the numbers were towards power, and some were towards your funds. I also found it weird that if you buy too many turrets, none of them work. I ended up having a bunch of unpowered turrets all over the map and had to try again.
The battle phase felt boring. The enemies have no health indicators, and I have no actions to complete, so I got a little disengaged. Maybe the enemies could have a chance to drop money or powerups that I can click to collect? That way the player stays engaged during longer fight sequences. The battle sound effects were great, though.
Otherwise, this was a good take on a tower-defense game. The bones are there; I think you just need to make some little changes to make the gameplay more engaging!