I have built a levinson rev 2 I think as well as a nyquist (converted to levinson layout) and unfortunately my cat just broke mine (don't ask). I was super excited to see the latest revision of this has usb-c connections (trss seems weird) and hot swappable switches (I would pay so much to upgrade my current setup with that).
Maybe it's just my hand but I hate columnar staggered boards. When I rest my fingers on a desk, they sit in a line. I don't get the popularity of boards like the li ly58 or iris or whatever not because they're bad boards but because they feel uncomfortable to use. I've been looking and there doesn't seem to be a single alternative to the nyquist out there. The foldkb is interesting, but what it makes up for in keysets it lacks in uniformity of layout. I just find it really sensible that every button is shaped the same as it aids my forming muscle memory to not have to consider differing sizes of keys. Think about learning to play the piano; it would be weird if the keys were also different sizes.
I hope keebio brings this back because it's an awesome board and perfectly designed. I would think the lack of businesses selling this layout puts it at an advantage, but I haven't seen the sales numbers. In the meantime, I'm going to have to research hand-wiring boards.