As I wrote for the Zombie boss, I am working on a system that adds bosses with levels and accordingly scaling properties and loot.
I also want to work on random dungeon generating. It is planned to expand the normal dungeons with the one spawner and similar to the "end stronghold" to generate dungeons of different sizes with custom loot and many mobs.
I also want to add my own plants where you can harvest different magical flowers.
I would like to revise the Blast furnace so that it becomes multiplayer compatible.