I found a small Towny and SMP server that feels really friendly and calm. The big rule is no griefing and no stealing so you can build without stress. They also say there are no resets ever so your stuff can stay for good.
It is chill but still kind of competitive in a casual way. The community is welcoming and people are around in AU EU and US timezones. At peak times they can get over 20 players so it does not feel empty.
It has Towny so you can build claim land and grow a town. There are jobs plus MCMMO and an in game ranking system. You also get dynmap and player warps with player shops and a sell only server shop. It runs on 1.21.x and it also works for Bedrock players.
