I always have autonomy on because I like to let my Sims lead me in the direction they want to go. I prefer to let the story guide me as opposed to creating it all myself, and I want unexpected things to happen. Unfortunately, the Sims 4 doesn't have a whole lot of surprises and Sims act pretty much the same and all gravitate towards the same activities so it doesn't actually do much except send them into repetitive rampant cycles that don't make much sense. It was very different in Sims 2, lol.
But I've been considering playing around with the the autonomy and maybe turning it off for the selected Sim to see if I can find a balance between allowing them to find their own lives and guiding them enough to keep the ADHD behavior from driving me nuts. :D