I think you should reconsider and keep working on the concept of the game. It's polished, and the concept is simple; keeping the coastal area safeguarded is a great idea on its own.
The game might need a little more fine-tuning on what the tower does and explaining it a bit. But, other than that, I really enjoyed the game. I hope you all reconsider the game because it's a pretty good tower defense game with a platformer perspective. It's a pretty good one.