I just finished this fun little keeb which I based off the Hummingbird, but I made it hot swappable, dropped the pinkies down more, made the thumbs more reachy, and spaced it for Chosfox CFX keycaps (tighter than standard Choc spacing).
It has a top plate and sound-dampening silicone gasket, as well as foam on the backside of the PCB.
Everything is open sourced on my github
I use a 30 key keyboard and do not use homerow mods. It is definitely possible. I use mods on a layer. Callum (sticky) style mods on a layer are also an option. You can see my layout here: https://github.com/jcmkk3/zmk-config