Nations
Nations weren't great in 2.0. I have no idea what 2.0 you're talking about. There was really only one nation in 2.0, Helvanthar. All the other communities were separate "nomad" towns, eg The_Grand, Dracko, New Nosaka (or they were in Helvanthar, can't remember)
However, we have been considering some way to join towns together to form a nation but it's extremely hard to come up with a viable way that doesn't suck like the Towny nations.
So yeah, nations are probably coming back in some way, shape or form.
Postboxes
No, just no. A quick, cheap tool for people raiding letting them empty entire storage rooms in seconds. It eliminates the whole transportation aspect of Minecraft when you can just safely send stuff across the map and store items in them (through friends or alternate accounts)
Gold currency
We did really consider keeping the Gold currency for this new server but we decided to go with emeralds.
- Using materials found within Minecraft promotes X-raying
- Duplication bugs can easily cause havok
- 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?)
Player shops
Yes, please. I do want this on the server. But the old ChestShop plugin that we've been using for over a year has a lot of flaws. We (I) have been trying to come up with a better solution but it's pretty damn hard to make them fair for everyone.