This is a good question, anon!

I prefer the appearance of the Sims in TS2 over all the other games. I like their cartoony, expressive faces. With the in-game tools, you can easily create unique-looking sims without needing to download extra sliders or anything. I tried TS3 for awhile, and I just felt that it was so difficult to get Sims to look unique or expressive (not to use the term “pudding,” but….yeah). The Sims in TS4 are an improvement to me in this aspect – I actually really like the way they look. 🙂 And of course, nothing beats the genetics system in TS2. I love playing families and seeing how genes and traits are passed down through generations, and TS2 basically mastered this. (You can probably infer that I’m one of those people who is deeply disappointed about the missing toddler stage in TS4. :|) Plus, I don’t think any subsequent Sims game has managed to make babies/toddlers as cute as they are in TS2. 🙂 

Then there’s the issue of the gameplay itself. I have a pretty good computer setup and a good graphics card (it loads TS2 and my 14-15 GB of cc in about 20 minutes, and runs smoothly for the most part). When I tried TS3, I installed the base game, World Adventures, and maybe two other expansions (Seasons? Generations?). I had hardly any cc installed, either. It would take forever to load, and even when it was loaded, the open world would take ages to render. I found it to be unplayable. TS2 crashes on me sometimes, sure – usually when I have too many Sims on a lot or fast-forward and try to pan over the lot too quickly or something. But for the most part I’m able to play my TS2 hood the way I want to, with the cc I want, without having to make too many sacrifices.

TS4, from what I’ve played, runs smoothly as well. I honestly haven’t played it enough to give it a fair judgement. I did enjoy what little gameplay I’ve experienced, though. I’m sure once more expansion packs are released and it feels a bit more “complete,” I’ll give it another go.

The major things I wish TS2 had from later games are the scenery from TS3 (*_*) and the ability for unplayed households (like townies) to age on their own. (I haven’t yet decided how to tackle the idea of perpetually young townies in my hood, while my own sim households pass through the generations…) But for me, nothing really compares to TS2. I’m sure a huge part of it is nostalgia, as well – I’ve been playing this game for ten years! – but hopefully this gives you some insight into why TS2 remains my Sims game of choice. 😀