Unless you specifically need the 8GB RAM (where Rpi 4 is the only contender in this range as of right now AFAIK), IMO for server use-cases it'd be better to consider either Odroid C4 or Rock Pi 4 - both offer better storage interfaces than USB/microSD natively. Also easier to run vanilla Debian/Ubuntu (or Armbian, which is very close to vanilla but can be easily built custom for either board preconfigured with necess…
I don't know if things have improved but traditionally every other alternative SBC had better hardware but was stuck in one image provided by the vendor that was never updated and buggy. Has the situation improved, i.e. can you just run apt upgrade on an Odroid C4? Can you run Arch on it?
The Pi is the only SBC with an excellent OS ecosystem.