Subsequent to my hip replacement and on-going back issues, belt carry of any kind has become untenable for long drives. I've switched to a horizontal shoulder holster for my P365XL, with two 15 rounders off-side, if I can't take care of what I run into, more gun(s) probably isn't going to help.
The shoulder rig took some doing to get used to, and requires plenty of dry fire draws to get smoothish, but it's hella comfortable for long drives. For instance, in the last two months, I've done two 20-hour round trips to Richmond, and a 27 hour round trip to/from Long Island. Complete comfort.