Some thoughts about persimmon care from an old repairman:
Try to keep the club face clean and avoid dirty balls when possible. Impact force of club on ball drives dirt into the finish and eventually you will erode the finish and then water gets to the wood fibers. What follows with regular play on an exposed club face is rot and degradation of the face area. The golf club will also get heavier from the water is absorbs than lighter as it dries out. You can keep the face alive when you see wear with judicious application of a good spray polyurethane after cleaning the club face a bit with sandpaper. Badly damaged clubs may require a persimmon graft or epoxy repair.
Watch the neck area under the whipping for cracks. Older persimmon was assembled without the benefit of modern epoxy and there are tremendous forces at work during impact especially in the thinner diameter top neck area. A loose shaft will eventually destroy a good club. Even modern epoxy can fail so inspect your woods regularly. Re-setting a shaft is not that hard if a crack is caught early.
Sole plates may work loose as a result of the lead weights moving during impact over a long period of time. Old Hogans are especially susceptible to this effect so watch out. Again, it is not that hard to set a sole plate and waterproof it with some epoxy and a coat of poly.
Lastly, check for a loose insert. Not only will you get un-solid impact but you risk water intrusion. You may be able to force some epoxy in behind the insert but it is usually better to remove it and re-set it.
I will be happy to respond to any questions you may have about repairs. Mike