I think they look awesome as always man! I personally don't have Naomi setup but will in the future due to looking at your artwork. My feelings are too have a bezel for every system on my setup as if you didn't know that already from all the console systems that I been working on. I think the majority out there just use MAME but I am doing my bezels for me and I enjoy doing them so do what you would want on your setup is how I approach it.
Thanks!