No the add on pack will be all white/dark grey too. It's mostly just going to be extra things that are interesting/fun and/or things needed for other physical layouts like 1800 for example, plus a selection of blank/generic keys for those that would rather not use US/GB specific keys, Windows legend keys, etc.
I'm just trying to tone the extras down to get a lower cost so it will actually make MOQ as well, but still trying to balance having all the right keys so there is enough interest to make MOQ... it's tough.
I will do some other colorful smaller sets in next minipacks in a few month.