As a mini-chess enthusiast, I love this game!
The art is amazing, and the idea is ingenious.
Maybe, in the future, you would consider implementing the "Chess Attack" 5x6 variant, and having a steam release - I would willingly pay 5$ for this little beauty. (Boosty doesn't accept PayPal payments =(( ) Or, maybe, you can put here "pay as you like" option.