It would be easier when dealing with existing keyboards, group buys, and such to have a palette that includes only the handful of currently interesting colours.
One possible way to implement this, without having to add a full-fledged palette editor, would be to generate a palette consisting of exactly the colours present in the current layout. That is, the user's workflow would be to colour any items on the layout with the desired colours, and then select Color Swatches → Colors in current layout.
It would be easier when dealing with existing keyboards, group buys, and such to have a palette that includes only the handful of currently interesting colours.
One possible way to implement this, without having to add a full-fledged palette editor, would be to generate a palette consisting of exactly the colours present in the current layout. That is, the user's workflow would be to colour any items on the layout with the desired colours, and then select Color Swatches → Colors in current layout.