Answer to the one set of wheel and two sets of tires. I do that now but plan on a second set of wheels in the future. But for now I ride mostly road so have only switched a few times in the last two months. One trick I use is to keep the tubes inflated enough to stay in the unmounted tires.
The rear through axles is a pain and I still have not mastered getting it back on. Off is easier. May just need a second bike more gravel touring.