I found a vanilla survival multiplayer server that lets cracked players join. It usually has around 20 to 30 players so it feels busy.
The community is active and people are on a lot. It sounds like the main point is just normal survival with friends and having fun together.
Headrest SMP is a Paper server on 1.20.10 with a few quality of life plugins and an active community. It uses Terralith and other structure plugins so exploring and building has more stuff to find.
The server is roleplay focused with lore and factions. People try to be friends and build together but there are also wars and fights when groups clash. PvP is more of a side thing but it can still happen.
There is a safe zone at spawn where players can build shops and hang out. They also use the Simple VC mod so people can talk in voice.
The server has rules and plugins to keep fights fair like no elytra during combat and combat logging protection. There is also /sit and more plugins. It runs on a dedicated machine with 20GB of RAM and a 5800x3d CPU to help reduce lag.
ArcticMC is a new survival server that started only a couple days ago and it feels pretty calm and friendly.
It is an SMP with Towny and factions so you can build a town then team up with others or try to take and defend territory.
PvP matters here but they use an honor system that is explained in their rules so fights are meant to stay fair.
You also get McMMO skills so you level up stuff like mining and combat while you play and you can unlock special abilities.
The world uses Tectonic generation so the terrain looks realistic with big mountains and valleys and lots of nice places to build.
They also have custom items and even furniture that is entity based and they plan limits to help prevent lag.
I found a new SMP called Overstressed and it is doing a big launch on February 22nd at 3PM GMT.
It has a custom questline with over 250 quests so you always have stuff to do. There is a player run economy with shops plus a currency system so trading feels like a real thing.
The staff made a massive spawn that is meant to be explored. When you leave spawn you can choose your path like taking a bridge to town or going down into the forest. There is also a road network that connects places and they even give starter spurs so you can get a horse and start traveling.
I found a really chill Towny server called GamerHub Towny. It is pretty new and it started as a server for streaming but now it is trying to grow into a bigger community.
The world has no resets and the rules are simple. Griefing and stealing are not allowed so you can build and relax without worrying.
It has an ingame ranking system that uses ingame money. There is dynmap so you can see the world. You can use player warps and player shops. There is a sell only server shop too.
Jobs are on the server and MCMMO is included. It usually has a few players online but when the owner streams on Twitch it can hit 10 or more.
It supports version 1.21.10 or similar and it also has a Bedrock port.
Eventide SMP is a brand new Minecraft server that just released. It is cross platform and it runs a semi vanilla survival style with only a few quality of life plugins.
It is whitelisted so you have to apply to get in. The server is built around trust and it aims for a mature respectful community that wants to stick around for a long term world.
There are active events to join and the economy is player driven with shops and trading like Hermitcraft. If you like community survival and steady progress this server is trying to be that kind of place.
ArcticMC is a new SMP survival server that mixes Towny and factions. It feels chill but there is still territory drama if you want it. You can build a town team up with alliances or go solo and claim your own space.
PVP matters here and they push an honor system for fights. The details are in their rules so it is not just random chaos.
It also has McMMO so you level up skills while you play like mining combat and more. There are custom items too and they even have furniture that is entity based with plans for limits to help with lag.
The world uses tectonic generation so the terrain looks big and realistic with mountains and valleys. The community is meant to be calm friendly and atmospheric so you can grind build or just vibe.
Aegea is a Spigot survival server that feels like classic SMP but with a few plugins to make it smoother. It has a simple economy and ranks and it is built around people playing together over time.
You can use /help to see commands and /back to return to where you died. You can set homes with /sethome and you can do teleport requests with /tpa and /tpahere. You can also /rtp to get sent out into the wild.
Making money is a big part of it. Players can set up trade signs to sell items at their own price and they can use /sell and /sell hand too. Chests and doors can be locked with /lock and if grief happens staff can roll it back with CoreProtect.
Ranks go up based on playtime milestones starting at Nomad then Peasant then more like Artisan Knight and Noble. Each month there is an election for Premier and the winner holds it for one month. Players can also join teams that share a name a home and warps.
The rules are simple. No griefing no stealing no PvP without consent no spam or advertising no game changing mods or hacks no lag machines no toxicity or NSFW stuff and just have fun.
I found a server called V+ SMP and it is like vanilla but expanded so it still feels normal to play. You can join with a normal Minecraft install so it stays simple.
It has improved vanilla style features and a bunch of quality of life changes. The main vibe is geo political towns and nations where people can team up and do diplomacy and stuff.