I found a decently heavy modded Minecraft server called Dopecraft 420 and it is looking for more players. The owner goes by Chase and most people call him Coop and he seems friendly.
The server runs Forge 1.20.1 and the modpack leans hard on big mods like Warium, Valkyrien Skies, Create, Mekanism, and Biomes O Plenty plus a lot more.
Anyone can join and there is optional creative building too but it is still a work in progress and they want to improve it over time. They are also looking for people to help manage the Discord since the owner is not great at it yet.
WebsiteDiscord