I played base game vanilla for months, and I loved it. Then I decided to check out some CC and gameplay mods (had a ton for Sims 2; game could easily take 20 minutes to load). I'm not going back; tons of CAS items and gameplay mods, especially ones that flesh out occult lifestages. I don't need them to play the game, but using that logic I don't need to play the game at all. It adds to my enjoyment of the game, so I will.
I've never understood the mindset of not wanting to use mods because the developers should be the ones to fix/enhance gameplay. Yes, they should, but if they haven't done that to my satisfaction and a modder has, why shouldn't I use the mod? Spite won't improve my gameplay. I don't even mind running around looking for updates after each patch, especially because half the time the patch breaks something new which a modder can fix in a couple days.