I played the first two. The first one being on DC, and the second one being on PS2, but I haven't bought the 3rd one. From what i've read its better and worse, kinda like what you're saying. I don't know, i've always liked the aspect of that series in what it lets you tune, but always racing at night kinda gets to me after a while. And i've always thought the AI in that series was a little suspect.
And believe it or not, I've actually been on the highway system in tokyo this past summer, and it truly looks just like that at night. I was cracking up when we were on a bus in tokyo going down the highway. The barriers and the lights and dead on.