The sim AI isn't that good. Even with MCCC installed, they still go off and do things that are counterproductive, out of character, or downright wasteful. And not even in a fun, interesting way, like TS2. No, it's more like the story progression of TS3, where you would leave a household for a couple of sim days to set another sim up, and you come back and that first sim has some butt-ugly townie moved in as their girlfriend that you now must break up with and kick out to make way for the roomie you intended for your sim whom you've just spent the last few sim days setting up (Can you tell I hate TS3's story progression?). Therefore, I just turn autonomy off...if only to keep Mom and Dad from going into Timmy's room to play Blickblock on the kid's computer for absolutely no reason...which will still happen if I leave the lot with one sim and come back a little while later (Yeah, the away system is complete hot garbage too.).
If the AI had some kind of way of using sims' traits and a history of player commands to generate each individual sim's automated behavior, I'd use it more. But it doesn't. It's just pure, mindless id. So, I avoid it now. Which makes me sad.
