tl;dr — Be a miner, fisher, rancher, or farmer; or, hire someone else to be one for you, and then become a railroad tycoon.

I apologize if the following idea already exists in some type of mod–I don't know much about Minecraft modding, although I think it's cool–but I've thought recently about what it would be like if vanilla Minecraft had a labor market / employment system.

For example, while sometimes gathering resources is fun and relaxing, it can get quite tedious if one wants to build something really impressive in Survival mode. What if we could hire villagers or other players to mine, fish, ranch, or farm for us, paying them in emeralds a piecemeal wage?

Surplus resources could be sold to other villagers or players to gain more emeralds, or, instead of being the employer, you could be the employee, working as a farmer, fisher, rancher, or miner for a villager or other player. Then you could buy resources you need (or buy rare items from shops) by selling those you don't.

Or, if you prefer, you can continue gathering resources by yourself, as you do now (the amount of resources gained by doing it yourself versus using the labor market would be comparable, so that it wouldn't incentivize one over the other but merely provide a change of pace / a way to mix things up).

This would open up all sorts of potential socioeconomic dynamics, as it would make villages more central to the game, creating possibilities like railroad tycoons who can connect places of residence (villages) with places of work (farms, mines, ranches, etc.), and railroad owners could charge fees for commuter and commercial transportation.