Lord of the Rings Online is free to play (with high level content for sale), but it's an MMO and those tend to get a little grind heavy. The problem is that multiplayer RPGs are usually either MMOs or Diablo clones, and either way they involve a lot of grinding for levels and loot. Still, it's more challenging than the Sims, it's set in Middle Earth with bunches of characters, and it has multiplayer content. No guns, no sci-fi, nothing as complicated as Civ, and it's not turn based. Might be worth checking out.