The biggest problem with this and all sims games is that you never have enough time to do anything.
Lets just get down to it. The game is a resource hog. Taking forever to load (and my PC is far from slow, its new).
With the usual expansion packs filling up your hard drive which add only minor improvements but the main issue is time management.
You get your house build, decorated. Now you need a job. You find one and it starts at 6 am. But time goes so fast in this game you have no time to enjoy it. Fancy a trip to the shops? You have to factor in travel time etc. You have to get up extra early as by the time you sim has got up, had a piss, breakfast, an hour has past.
A small tweak to the time system would be handy. Instead of minutes ticking away like seconds. Give me more time to enjoy things. I also haven't yet travelled around the world because when it says 3 day holiday, I know it will be gone in a heartbeat and I have to return.