I'd honestly like to issue a formal apology because I know I've probably complained a lot. I'll try to be more polite in issuing constructive criticism, but I'm sorry if I've come off as rather immature. I got a little too eager when I first joined the forums :# but I digress. I don't hate TS4. That doesn't mean there's no room for improvement but there are still things worth experiencing in the game.
CAS, for example. The layout is very easy to use and the options for adult Sims are simply staggering, particularly in the facial department. Lots of cheek, nose, lip, and head types. The sliders are also top-notch, allowing you to sculpt your Sim to your heart's content to get it exactly the way you envisioned. In addition, the lifting of gender restrictions on clothing a while ago was a particularly excellent choice, allowing for much more freedom when creating Sims with clothing that fits their interests.
Vampires are another aspect of the game that has been particularly well-done. The facial details are awesome, the power/weakness system is very well thought out, and of course, more ways to WooHoo are also a delightful addition. The Ask Permission interaction for drinking is also quite excellent for Sims who have a high relationship with each other. The Command powers are helpful for dispensing justice on Evil Sims. *cough* Malcolm Landgraab *cough*
The Scientist career is honestly one of the most fun careers to play. Being able to create inventions and use them on other Sims is one of the best parts. The Satellite Dish is handy for bringing aliens around in case one wants an Alien Baby. The Cloning Machine comes in handy for ingredients, and it also makes for more drama if you end up with an Evil twin. And again, the Mind Control ray is useful for the above reasons in the last paragraph.