I’m using a SuperMicro A2SDi-4C-HLN4F for my NAS.
It takes like 20-30W with 4 3.5" SATA HDDs and one M2 SSD installed. It has IPMI and I’m running it with FreeBSD 13.2, works like a charm. You just need to be aware that you need to adjust the SATA ports in the bios in order to use all 4 of them, by default only 2 SATA ports and the SAS interface will be enabled.
The temps are fine on the cpu without fan - I only have three fans in front of the drives.
Getting a better rack. My 60cm deep rack with a bunch of rack shelves and no cable management is not very pretty and moving servers around is pretty hard.
Hardwarewise I’m mostly fine with it, although I would use a platform with IPMI instead of AM4 for my hypervisor.