The big one is desktops that I like, working out of the box: Cinnamon, XFCE or even MATE (can install more, of course, but these ones are supported and tested). XFCE is really snappy and lightweight, whereas Cinnamon is pretty polished and will also be familiar to folks coming from Windows (nice distro to recommend for that, for people with limited Linux experience).
Another big thing is not having snaps forced down my throat like Ubuntu increasingly seems to do. In that regard, Mint is closer to Debian, although if you want to, there is nothing holding you back from using AppImage, Flatpak or anything else (even snaps).
Compatibility that is otherwise pretty close to Ubuntu, as well as a long EOL period: after the demise of CentOS, Ubuntu remains one of those distros that you can just "install and forget about" (hopefully with regular updates), both locally on your workstation and in any of your servers. I can even base my containers on Ubuntu/run it on servers (pretty much every provider has support for it) but use Linux Mint locally and have pretty much everything work.
Now, frankly I could also opt for Debian without too many issues (they also have an LTS variety, albeit less advertised), but Mint is basically Ubuntu without some of the things that annoy me - boring and dependable, mostly just works.
Only annoying thing: if you ever need to setup an apt repo that points to packages that are compatible with Ubuntu and the script for doing that gets the release codename, it might get one that doesn't correspond to the correct Ubuntu release, but instead will grab the Mint name. Sometime need to fix that manually in the apt repository list with a text editor.
I install the system using the Xubuntu ISO. Presumably if you install the xubuntu-desktop package on some other flavor it will be similar but if for instance you installed it on top of e.g. Kubuntu you might still be getting KDE services loading when you log in.
I'll try this for my new NUC, thanks for the tip!