...two of which have near-identical layouts, and one of which I'm typing on now!

I have literally dozens of keyboards: mechanical, split, ergonomic, mobile, the list should end but it doesn't... And yet I'm typing on this split, tented, rubber dome Microsoft Sculpt Ergonomic. It has tactile keys, and such an extraordinarily low profile that I can type with it on my lap with my wrists pointed down. It has function keys and I don't need a second layer or FN key to access home/end/pageup/pagedown. The spacebar is split so it doesn't bind like many single-body split keyboards. And it's wireless!

This mass-produced, reasonably inexpensive keyboard is not perfect in any way, but it's 90% to perfect in almost every single way.