Hi,
I've frailed resonator banjos for the volume, but not for the tone.
I remember seeing Cathy Fink, and Eric Nagler frailing resonater backed banjos. So there.
As far as skin heads go, I've installed and played on them, but I wouldn't suggest it unless you're playing an older open back like a ninety year old Fairbanks, Bacon and Day, or Cole, or something like that, which would almost demand a skin head,(and nylon strings) to sound right.
They are murder to put on, and have the annoying habit of ripping just when you've got them perfectly tightened. Not something to look forward to when you've just paid fifty bucks canadian for the damn thing and the customer you've installed it for is expecting to record with it the next day.
Climate change plays hell with the tension, too. Fiberskyn is okay for most things.
Mellow tone can also be enhanced with a no-knot tailpiece, instead of a long-tongued bluegrass tailpiece.
Yuh.
Owl.