One suggestion is to look at getting any useful docker container up and running first to get a feel for it, then pivot towards heavier lifts. Self-hosting emails is going to be a headache as others have said, and monero nodes sounds like it could be a technical as well but that’s admittedly an uneducated guess.

You can look at the recent selfh.st poll for the most popular docker containers, see if any strike your interest and start there.

I use it. I think it was a hardening recommendation from lynis IIRC.

I definitely experienced a lot more freezing on my laptop after installing it (it’s a memory hog) so I upped my swap and things are back to normal.