Thanks for the suggestion. But that opposite is generally the idea. To have a server that is always on for image uploading, syncthing, webdav, vpn and whatsoever, that is build for low energy consumption (only 2,5" ssd with cache disks, so they are mostly spun down) in a small case.
I use the SilverStone SST-CS280 case that is a brilliant micro ATX Case with 8x 2,5" hotswap). Only the cooling is bad, as there is no active fan for the hdds, and using 15mm 5TB disks means they are nearly touching each other leading.
The whole setup with a good Core i7 CPU is idling at around 25W consumption and all services (more that 30 docker containers) are always available.
I have another server with good cooling, a lot of CPU and graphics power and storage that is only activated on demand.