Getting back to the Chiappa Rhino, I've handled one but not had the opportunity to shoot it. The grip angle is odd but not totally off-putting. The fake hammer-cocking lever seems like a dumb idea to me. Make it double action only and be done with it.
Perhaps simplifying the lockwork would improve the trigger pull which, as it stands now, isn't very good. Short, but stiff and a bit vague.
As you say, make it in steel and make it 7 or 8 shots and you've got something.