Not sure if this is of any help or interest, but, the 2 times I ever did an F-hole I used a pin router setup.WOW! I forgot how thick that top is. F-holes are painful enough to do by hand when the top is only an 1/8” or so, I can’t imagine the agony of doing those whil trying to keep the cut perpendicular to the face! Nice work!
I take the body template and cut in the f-hole. This I glue then to the body's back.
Then I use a drill rig, where I can put in a router or drill. First I put in the drill and drill a 4mm (or whatever size fits the smallest radius of your f-hole design) hole in the wooden table of the drill rig. Then I lock the settings and change the drill for the router with a 4mm router installed.
In the hole I put a 4mm rod, which is just high enough to be used as a guide for the f-hole cutout in the body template I glued on the back of the body.
Then I rout the f-hole in multiple steps.
Disadvantage is, it is hard to sand the f-holes sides smooth, as you can only access from the top. But it is a fast and accurate way to cut an f-hole.