I actually love the colors... red bellows are awesome and the white makes for a nice contrast. You may want to consider offering it in natural wood look but also painted black or white on request. Something unusual like that can actually be a good selling point. At least it would be for me.
I agree with Ian C that bigger locking knobs would be useful. The ones on your prototype look too small to operate reliably when you're under the dark cloth. Making the bellows detachable is a good idea too, though I have no idea how hard that is to realize or if there are any standards.
I don't know about bubble levels... of course they're useful, but do they fit with the style of the camera? You'd need to find something small and unobtrusive that fits with that old-fashioned style of the camera, not one of these massive neon-green things.