I feel like the gameplay is a tad bit boring, even as an idle clicker. Mainly the fact that there's no special "rewards" and you can already see all the endgame stuff (all they do is provide more sand castle production).
Also, I'm not sure why the upgrade UI has a progress bar that takes so freaking long, it's kinda annoying.
The theme was met, the art is perfect, and the audio is great for this game.