Not GMK, but Akko keycaps.

Double-shot and ASA profile if you're curious. Seems like I've found a fellow keeb enthusiast!
Other puzzles - definitely! The only thing holding me back is that those would take a bit more time as I have to measure the stickers for them specifically. I have done other sticker mods in the past though, for a 4x4 and a fused one too.