The biggest thing I would like to see with this is something like faction, but not exactly factions. I would make it so there is some sort of npc that the owner has to spawn in with an egg that would allow you to make a guild. To make a guild you would have to be like level 100+ and have 20 diamonds. If the npc allows you to make a guild it gives you the choice of a couple items which spawn in different types of castles (This is why you would need so many diamonds and levels). I would also love to see an option in the server properties that would have the option of choosing which blocks rangers can climb and can't.