RPG Server Update [MUST READ]

I'll start out from the basics:

There'd be 4-5 different tribes, empires, whatever you wanna call them. The original time period/theme of this server would be back starting in the Stone Age, so 4500BC - 2000BC. Now, the tribes would be like: Mongols, Aztecs, Egyptians, and Romans. The server would be whitelisted so you'd need to apply for one of the tribes and once accepted you'd be in it and could get on the server. Now, you'd start out in the Stone Age. There'd be classes, and basically would all be dependent on each other. It's a nice survival. For example, a blacksmith/craftsman is the only class that can make stone+ items. Everyone can access the crafting table (to make minimal stuff like wood tools), but to get a stone item you'd need a blacksmith. Then you'd have your average warrior, archer, builder, tribes man, etc etc.

(Classes are being discussed now for the server. If you have ideas, post them here).

Each tribe is separated by about 1000-4000 blocks away. Why? Well, it defeats the purpose of survival if they're only a few blocks away and stealing/griefing would happen on a daily basis. This wouldn't be fun at all. The objective is to survive, and go throughout the ages by leveling up. We have yet to decide on how classes will level up; whether it'll be money based, item based, exp based, etc. We're thinking it'll depend on the class, so for example, a Warrior will need exp to level up, and a blacksmith or w/e will need items. IE; 5 wood planks, 3 wood swords, etc.

The three ages would go from: Stone Age -> Bronze Age -> Iron Age (more to be added if the community grows enough). Basically, that's the idea. Each tribe will only have one thing built by admins: their spawn. The spawn will be worldguarded (and the ONLY thing worldguarded), but will contain the areas where you sell items, level up through classes, and read all information via commands, etc.