Great! Overall it's a really neat tool. It's a unique concept that makes the whole "palette generator" thing infinitely more useful.

I've got just one critique. I get that this tool was made with a specific rather limited game engine in mind, but it would be nice to be able to generate palettes with more color options. An option to choose to generate palettes with 2-5 different colors would be a great addition. Nothing crazy, and it would even work with the example image with the hearts that's already used.