I am going to put forward a few suggestions for consideration if we do go for a vanilla Minecraft server. Mostly for quality of life changes.
First one is looking at some data packs, such as some of the ones from this site (https://vanillatweaks.net/picker/datapacks/) I like the idea of some of these, like 'dragon drops','multiplayer sleep' and 'double shulkers'.
The other is maybe doing research in to a seed, so most of the biomes are a respectable distance from the main build area.