This is really cool, but I found myself battling with the UI more than actually enjoying the results... There's no way to type in exact HSL values (have to use the sliders), no RGB / HEX colors (except for the one "lock color" option, which only supports HEX but not HSL or RGB...). CMYK is an obvious suggestion following those

Could also probably use additional "locks" for keeping the same starting and ending H/S/L/R/G/B