Hi, welcome
I'm not sure there are any other layouts of much interest. My hands are getting pretty accustomed to my customizations atop the Planck layout; it's sufficiently minute that it pretty much needs to get customized in order to be much usable.
My "cool bits" are that I added in a couple of "random" keys; they use keyboard timer + linear congruential RNG to generate fairly random numbers, so I can hit the "random numbers" key, to get 680766910078581035059920902 random digits, and "random alpha" to get stuff like azupqxmyepaxtopaywrxrvidrzatsedwjcr. Not SUPER random, but good enough to fill in blanks when they need to be filled with 'trash'. :-)
It doesn't mean I have much insight on integrating code for new, oddball keyboard platforms. But I have been playing with qmk a fair bit ;-)
