Like all things in Minecraft,,it depends on what you're looking for. If you're looking for a hard-life, full of adventure and danger, choose the Dunedain. If you're looking for a life of peace, go for the High-Elves. If you want relative peace, but still want to battle invasions, choose Rohan, etc.
But Gondor probably has everything you're looking for, one way or another. They're the most diverse Faction so far, due to the Fiefdom Sub-Factions and all the biomes that come with them, only Harad comes near their diversity.
Personally, I go with Dwarves or Rangers.