I think Necesse could be a nice fit!
Considering the game is on 1.1, the sandbox features are awesome! It already has lots of variety for materials and decorations, the gameplay is highly customizable (specially with how you can manage your villagers/the NPCs' behaviour), and how your village and its inhabitants interact with the surroundings you build. I really enjoy how you actually need to build and decorate houses for your settlers to live in, since that absolutely impacts on their mood, and it makes me feel like the time I dedicate to make something nice is actually worth it gameplay wise!
Honestly, with how passionate the sandbox community can get, I can absolutely see people making mods for custom bosses/missions for the elder to give you, mounts, decorations, tools/gear, crops, maybe even some stuff aiming to expand the things the game already has, like improving/diversifying the settlers' ai, adding new creatures to the current biomes, even new biomes and improvements to the world gen! There could be mods for improved and more diverse character and npc customization, since the options are very limited at the moment (but Ig that's a pretty minor thing about the game at this stage, so who knows!)
Sorry for yapping, I really like the game lol
