> If you want up-to-date software from your package manager, use a rolling release distro. Otherwise the best you can do is something like a base setup and then side-load the software you want. This problem has been identified to the point where there are several brew-like systems (and things like snap as well), but no clear winner yet.

I use openSuSE Leap with a bunch of OBS (build service) repos added. I get a nice stable base OS with updated packages when I want them. And it runs KDE/Plasma nicely, too, and not as an afterthought or something like other distros.