Current plan is powerlet outlet on bars, inline fused direct to battery. One bar/tankbag device plugged in at a time. This is can easily be adapted to plug into eastern beaver fuse panel if I need to add that in future, and add more circuits.
I'm aware (from house wiring) , that sometimes the limiting factor is your overall capacity (the master fuse/breaker in your panel), and sometimes the limitation is space for additional circuits.
Right now, with the stock, 17 amp total output from alternator, I'm trying to not exceed that capacity, so purposely limiting the ease of adding circuits/devices.
Besides, part of the appeal of the motorcycle is to get away from all the electronic gadgets. Which is why its taken me this long to even consider a motorcycle mounted GPS (but I've gotten addicted the usefulness while driving a cage, especially around where I live, where street signs are often small, missing or hidden by vegetation).
So, yeah, while fabricating the switch blank to powerlet socket adapter, I'll probably make two, since I have two unused switch blank slots on my bike, but one will just get stashed for now, until I upgrade charging system, and then want to add additional circuits.