The only thing that stops me from playing the sims 2 as my main is that Sims outside of the current household don't age and if you ever achieve platinum status (which is surprisingly easy) there's no challenge in the game anymore. Because needs barely matter anymore.
I was once trying to do a "realistic" run with my sim starting in a trailer park and eventually working my way up the property ladder. I got platinum before i moved out of the trailer.
3 would be the best if it was stable and had the moodlet system of 4. At least for how I want to play the Sims.