I really enjoy making sims in CAS. I'll sometimes spend hours in CAS making sims.
Other times, I'll build. I'm not that great at it. And I'm assuming decorating is part of building? Well, I get lost for hours and hours decorating houses.
And I love playing the game, too. Full Autonomy, I have taken lately to enjoying letting sims do their own thing and see what they get up to.
I really enjoy rotational. Might be my favorite style of play lately.
I enjoy Challenges, as well. I am usually doing some form of a challenge or another (FYI, any Challenge creators out there... we need more rotational challenges, just an FYI).