Rpg Must-Haves:
Mine or Quarry.
Bank/ money
Save points (save variables works nicely)
Shop
Tasks to open new areas
Skills (mining, smithing, fishing, etc...)
Optional things that people like:
Weather conditions
Goals (ex. When you complete a quest, a reward or trophy will spear in your house.
Zombies/ dungeon raids
Freeplay (no the entire thing is not layed out for them in a specific order)