I'm one of those guys who doesn't want the look without the function. So... the thicker grade leather would be better.
On a positive side, I found some really nice ruby coloured felt for backing. I had read somewhere that some of the more intrepid highlanders/Jacobites used redcoat pieces to pad the back... dunno if it is true or not, but should look good enough. I also picked up more brass upholstery nailes/studs/tacks (whatever you want to call them). Round headed... so I can change up the design for the face a bit. I have enough felt to do at least 4 layers on the back. Should work ok.