For me TS4 is good, not great but good. I find myself getting bored with the game after a while but maybe because I only have the GTW pack. I do like most of the gameplay, but some things make no sense to me. Like why do Sims always have to hug each other while the other Sim is eating? Happens 95% of the time. Another is if they get a plate of food, they always will go where other Sims are even if it's a bedroom and will sit on the bed and eat. I also hate when you invite Sims over and the visiting Sim will go for a jog for most of the visit. The Sims seem like they get stuck in patterns, doing the same interactions over and over, and seem quite mechanical in their day to day lives. There are more annoying things I could say about the game but I won't.
Overall I can play it for a few hours a few times a week and that's about it. TS4 just lacks a certain personality. The game isn't as quirky as TS2 was and I usually go back to TS2 which is my favorite game of the series. I still find myself playing TS2 for hours and hours.