Pretty good, most of the Suika games I've played were items (largely fruit) of the same general shape, but I like the idea of shapes being vastly different, and the grist shapes are a pretty smart one. 

On another potential note for this dev, I'd like to see a Suika game where the border is instead of a box, either a circle or triangle. It'd be neat to play and presumably not much more difficult than this.

Anyway, I'd be interested in seeing what else you put out. Good stuff.