There are lots of mods you can get to improve TS4, but you're right, it's missing something fundamental. Even things like genetics are so dumbed-down as to be almost pointless
While it's mostly about the stories you create yourself, there is actually a storyline you can play through! Each of the three default neighbourhoods has a specific order of events. You kinda need a walkthrough to know where to start and when to switch families, but it's all there for the playing. I didn't even realise that until last year, and I've been playing TS2 since launch