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.
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
I've had similar experiences and have had much more luck with combo mods. This article describes the idea and it works well. I use a slight variation in that all of my combos are one shot so you're not having to make weird finger contortions to reach things, just hit the combo and then the letter. https://jasoncarloscox.com/blog/combo-mods/