I've got a few different boxes at home. From an old desktop that I can fit a fanless nVidia GPU in (for Frigate) which i'm running unRaid on as its got lots of slots for HDD. But I kinda hate unRaid, so have since gone the TinyMiniMicro route (ala ServeTheHome - https://www.youtube.com/watch?v=bx4_QCX_khU&list=PLC53fzn9608B-MT5KvuuHct5MiUDO8IF4) and have 3 EliteDesk Minis.
They're running XCP-NG with a Xen Orchestra VM built from source to manage the 3 boxes. On that i've got a handful of VMs, a couple of generic linux builds one for docker, and then 3 VMs running a k3s cluster and i'm slowly migrating services across to. Some stuff like Plex / Frigate etc does better with a GPU though so i'll keep the unRaid box around running those sorts of things there.
Anywho, with the small form factor PCs - Trade Me's auction history is terrible so even though I only bought them part way through last year I can't find the vendor I bought mine from. They were really good which is why I wanted to shout them out - sent a replacement fan & stick of RAM within a day of me emailing a problem with what they'd originally sent. They show up on TradeMe & Facebook Marketplace all the time, they're all ex-lease from corps I'm guessing.
I'd recommend these boxes over a NUC because they're cheaper, and by far over a Pi because they are so much more powerful for a similar price if you can get a good deal on a used one. They're not much louder than a Pi (and because they don't use those tiny fans the noise they do make is less annoying) and they're still reasonably lower power use from the wall too.