The AI don't deal well with upgrades, so try to avoid too many upgrades in the career mode if possible and in free play limit the PI in the options to the number your car has (ie 999 > 535 or whatever). In free play most of the AI will go under your PI number and you'll experience much cleaner races using this method, if it's still bad (Vintage Le Mans Sportscars can be a mess) try lowering your PI.
Yeah it's pretty bad still, would be nice if they would make their safety rating stuff actually work. I still brave them out somewhat regularly because I find it kinda amusing most of the time, but there are definitely nights where I wonder why I bothered, and they are pretty depressing really when you watch how bad people are in a "this is why we can't have nice things" kinda way.
I've driven a few laps of it in ACC. First of all, as far as I can tell, you can only drive the 24 hour track, not Nordschleife without the Nurburgring GP section. Apart from that, it felt very similar to the track in FM to me. There might be some small differences in the shape of everything in places, e.g. one corner where I struggle to not run wide on exit onto the kerb in FM, I found myself exiting noticeably short of the kerb in ACC, so maybe that edge of the track isn't quite in the same place in the two games. But if you just pick one of the games and only play that game, and get used to its version of the track, the experience is going to be largely the same. I haven't compared the night versions as I don't like driving at night, so it doesn't really matter to me.
I would tend to be at the opposite end of your spectrum. I think ACC North Loop is wonderful. It surely is the newest version with lots of repave and less graffiti. It's a nice edge of your seat feeling and changes to the car setup make noticeable differences. Sure the FM version is Nords, you still get the feeling of being on track but I would have a hard time saying that FM is better than what was just put out today. Those pyramid top huge curbs that FM decided to put on the track are just one example right away.
This is the sort of thing I mean when I say that you just learn the one in the game you're playing and then it doesn't make much difference. In FM, I mostly avoid the kerbs because if you have the car tuned to be on the verge of oversteer, which makes it corner the fastest on smooth tarmac, then touching a kerb on corner exit will make the car oversteer and lose time. So I mostly stay off the kerbs in FM, but there are some you can go on, particularly if you're not steering much. I drove the ACC version the same way I drive the FM version and didn't have problems with kerbs, but maybe if I specifically learned the ACC version I'd use more kerbs and then if I drove the FM one the same way I'd have a problem with kerbs that aren't a problem in ACC. But apart from one being more accurate, it really doesn't have much impact on the experience unless you're looking to practice for driving on the track in real life.
The lighting is so much better than FM7, but it can be inconsistent, especially with the specular highlights (FH5 does this better), and the HDR can go haywire in some places (Homestead at night under heavy rain, for example).
I think they went cinematic/realistic, and clearly wanted to separate from the FH style.
I tried RT performance, but now I play exclusively on Performance, as the game looks cleaner. Do this: With RT on, paint any car in chrome, then drive it and park it, say, in some section of the Nordschleife with lots of graffiti on track and trees around, then compare it under the same conditions but with no RT, just plain old cube maps, and notice how low-resolution RT reflections are.
