Wasn't clear if you can apply your own custom palettes. My biggest nightmare is making paid assets conform to a specific set of 15 + transparency colors for the sega genesis. Existing tools sometimes get the color wrong but don't let you easily manually specify an alternative. That feature would put you ahead of everyone else - especially existing free tools.
You can absolutely use custom palettes! You can load any palette on https://lospec.com/palette-list.
I think I will also add the ability to load custom palettes from local files the next couple of days :)