I don't keep a Swiss army knife set of distros anymore. I put tumbleweed on a USB. It's rolling so I update it when I plug it in, then do what I need to do.

I used to have a USB with Ubuntu LTS and whatever the newest Ubuntu was. Then another would get something else that I needed/wanted. I always ended up wiping the drive and adding the newest release every single time. I was always out of date by the time I needed one of them for boot repair or something. This was also a time when persistence... Wasn't very persistent. With tumbleweed I can install whatever I need and it's there next time. I'm sure you can do the same with any other rolling release, but tumbleweed is in my opinion on par stability-wise with incremental distros. It's my first grab whenever I need to check a PC. If I need another distro or boot USB, I can make it from this one with a second USB. I suppose the only thing I can't do is make a bootable USB if the computer I'm on can't access the Internet