If you could make any "simulator" game, what would it be?

Sad thing is WoW could already be that. But because all focus is on the last expansion, the rest of the vast game is basically dead and devoid of players. It's not "World of Warcraft" but "Zone of Warcraft".

Elder Scrolls Online has its fair share of flaws, but the "One Tamriel" update did make all content playable by all players. You see ESO players in every zone, not just in the latest expansion.

Warlords of Dreanor literally had this lol. You would manage a squad of npcs equipping gear and stuff and send them on dungeon quests. It would just give you a percent chance of succeed or not and you would hit go and wait several hours.