My main concerns were that, as roostrc0gburn pointed out, certain legends may not fit properly. Does Alt Gr fit in 1u, and does "Control" fit on a stepped key? It would likely be "Ctrl", right?
As for the Windowed Stepped Caps, I just realized that the original GMK Penumbra set has a non-stepped windowed Caps Lock, so I guess we might as well add the stepped one as well. Sorry about that.