I'm not sure what the tried alternatives are. I'm essentially looking for a single-board computer, but I'm willing to go all the way to a minipc if I have to.
Most SBC or small form factor computer which have at least 4 CPU thread, 4GB RAM and port to insert SSD/HDD should work. I've seen some people report they run Bitcoin Core with Intel NUC.
Perhaps a Mac Mini?
Considering it's relative expensive and it has Mac OS (which means less help or guide), i doubt it's great option.