add a Datapack 
to the Server what allows new types of structures to spawn as in bigger Villages and more like as in Dungeon it would be a create idea since it would be more funny to raid stuff or explore in Minecraft -> Build Limit change would also be a nice thing same is for claiming things on the Smp it would be nice if u could claim larger stuff 
#- Lunar Smp Idea
warped heath
narrow silo