... mmmmmm, ... beer.Most racks are easy to remove, rackless options tend to require taping the side panels on the rear (or dealing with them scuffing up). For me the rear rack also works as another crash structure, keeps the exhaust and rear off the ground.
I generally don't have the passenger pegs mounted (they hurt when they bite your calves), which means a total of 6 bolts have to be loosened to remove the Outback Rack I have. Possibly an option in your case as it shouldn't take more than 15 minutes to rack up.
Another benefit of a tool tube type situation is that you could put your tentpoles in there as well; right now I have to stash everything inside the panniers.
That said, my usual carry is (keep in mind, my camping stuff is small/basic):
Sleeping mat, sleeping bag, inflatable pillow, camping chair, tent (all fits in one pannier)
The other pannier is basically cooking stuff (stove, gas cartridges, cooking pot, cutlery), clothing (nice set, everyday clothing, shoes, slippers), spare space for food/drink items.
Ditching the cooking stuff and more minimal clothing I easily have space for loads of beer, that's what my packing on a more casual ride with the boys looks like. If you're mainly riding and camping all you care about is clean socks and underwear anyways. If you're out with a few mates for a day or 2-3, you'll have enough from my experience.
Must feel good to crack a river-cold can after a day of solid Africa Twin riding.