Would the Cambo Wide DS (non digital) be too big for you? I think it would do all you are looking for with helical mounts for large format film lenses, viewfinder, hand grip (of sorts), ability to take roll film backs, shift and rise/fall. I haven't used it directly, but I use the digital version.
Thinking about it, I'm not sure if it has the facility for ground glass and reflex viewer but someone more experienced with it could help there.
One to include in the list perhaps.
Matt