@Cinebar Then either you must have been very lucky or I have been very unlucky, because the routing in The Sims 2 drove me nuts sometimes. Especially in combination with where the sims would drop babies, teddybears etc in the house. The amount of times a Sims would pee himself because another sims had previously decided to block the bathroom with a helpless baby is insane. Then again, I might have been unlucky or my sims might have been incredibly stupid.
There is still hope that they fix the majority in patches, just like you yourself said they did with TS2 ;) The Sims games have never been completely perfect on launch... How many patches did TS3 have, over 90 I believe?
I do agree that even though it's great that they decided to make The Sims a bit lighter to play (saving every 10 minutes in TS3 because it could crash and burn at any moment was just horrible), they might have cut out a bit too much in some places. It's pretty obvious that the reason they did the routing 'differently' is to keep the game playable on low end pc's. And yes, that is pretty lazy.