I don't have your experience or knowledge on engineering/design but what would happen as far as shear stress if instead of the revolver firing from the 12 o'clock position that you lower it to the 6 o'clock position? Just looking at the design of the Break Top revolver it would seem to me that by lowering the firing chamber to the 6 o'clock would greatly reduce the stress on the latch while the hinge should be more then capable to handling the pressures of modern loads.
My thought revolves around the Chiappa Rhino design which just looking at it, I believe lends itself for a harder look in this purpose.
I ask you, what is your expert opinion on such and would it be worth contacting Chiappa to see if they might be interested?
Looking again at the Rhino as currently design, if fesible would require the revolver to be a double-action only (DAO) by my account, as the locking latch and cocking lever would interfer with one another.