A list of suggestions I think can greatly improve server experience as a whole

[yottabyte]

I think you missed my two biggest points there.

• Emeralds are the de facto currency in Minecraft, like it or not. I know they're kinda tricky to get your hands on at the moment but we've been discussing adding NPC shops that will trade various things every day/week/whatever for emeralds as an addition to the already existent villager trading.
  
• Having NPCs trade various items for money encourages different ways of playing the game than just caving and strip mining all the time to acquire wealth. Maybe gathering lots of flint from gravel or making bricks out of clay (deep sea clay farming anyone?)
  

We could just inflate the emerald economy using the NPCs to make them easier to trade with if that's what you want.

And no, gold nuggets aren't obtained in many ways. You either mine them or kill pigmen.