I can honestly say that I finally got my chance at playing vanilla Sims 3 once at one of my friends' house a few days ago. Let's just say I'm still not impressed overall, except for the scenery, (Water effects on the lakes/beaches could've been a lot better, too, but other than that, nice background stuff) but it's not overly abysmal as a game... though it is as just a Sims successor.
I had a somewhat frustrating time with the CAS... anyone who knows my style of simming knows that my sims have a "cartoonish" look to them, and I just couldn't achieve the effect I was looking for, even after an hour and twelve minutes of playing around with it. I'm pretty sure if my friend had the modified facial sliders, then I may have gotten what I was looking for. (That and if there was more room for having custom skins instead of just one type of skin overall.) Plus, it wasn't long after I finished the family that my friend's PC just conked out for some reason. I suggested he look for that frame rate mod just in case that was the issue, since that has been discovered that EA's bad habits of "fixing" bugs tends to work the heck out of a computer.
And surprisingly, create-a-style was sort of nice, seeing as it cuts back on having loads of junk files in the game. The gameplay, however, just seemed like the same thing all over again, with added tweaks. I'm better off just sticking it out with Sims 2, even though I know for a fact I can barely start that up without issues either.
With that, going back on topic:
If what the OP says is true, EA is going to have to do much more than just add on to the current Sims 3 to make it appealing to more simmers... if certain things about the game weren't so awkward and buggy without modding (in the vanilla state, the unwanted spawning/dying off of sims, lack of car animations, the frighteningly bad look of the offspring... not to mention their screwed-up patches), plus if they hadn't screwed themselves over in the past with the Securom fiasco and now with even more game patch issues, it would have been cool to have this particular game style as a stand-alone addition to the franchise. The whole concept of the game seems more like what they would've put in console versions anyways, just not a proper successor to the Sims.
I still say if they had a Sims 3 Bodyshop and the Create A World tool already available with the game they probably would've done better. Wonder what the next EP will bring... although I'm sure the ad that's out now is definitely not showing what may
not be included. We all know how that works, as always.