Ability to create and change relationships, and the ability of the game to recognize those relationships
Ability to create sweet looking Sims
Personality traits and lot traits
Affordable DLC
Ability to have everybody get along, and nobody fight or cheat unless desired
Ability to completely customize Sims, lots, and the world
Ways to connect Sims, like the ability to create groups and clubs
Excellent family tree that shows complicated relationships with many generations
A way to quickly recognize Sims (like a name label that pops up over their heads)
A way to easily get from one place to another without having to hunt around for the place (which for me is facilitated by maps and loading screens)
