Another stunning project. I can sit and gawk at those photos for ages!

No levers at all. The one shotgun I have seen with no levers at all was a Bernardelli folding single barrel where the trigger guard slid back to release the barrel. It was a puzzle for the uninitiated!

Whatever solution is found it will be an improvement on any lever system with those anti aesthetic protruberances on the action. Levers are one of my pet peeves, the other one is ribs.