It's the details that matter to me.
I love the attention T10 pay to trackside materials, grass, foliage, gravel traps, marble build-up etc.
I like the more quirky car choices. Someone at T10 is clearly an IMSA fan, particularly from the 70's/80's.
Dynamic weather & time of day is a step in the right direction. Same for the more structured online competition.
With that said, there are so many letdowns in the footage we've seen.
The lighting & materials (metals, carbon, plastics) continue to be off by a huge degree.
No one mistakes any of the footage for the real thing. It very much looks like a game, a polished one it has to be said.
GT7, FH5 and numerous AC PC mods have shown the importance of lighting to deliver a realistic presentation. At this point it seems clear T10 aren't interested in that aesthetic. Even something simple like the exhaust flames reminds me of a last-gen Grid or Project Cars implementation.
Car movement seems off in numerous videos. But you can't really judge until you get hands on. The lack of body roll, diving under braking, driver model physics (reacting to G-Forces), steering wheel animations takes away from the immersion. Particularly from cockpit cam.
I think we're looking at a solid game that will rate in the 80-90 range. But I still feel T10 are stuck in a no mans land where the major corporate, development & player focus is on the FH series. The best thing they can do (which I believe is planned) is to stick with this iteration of FM for the entire gen. Build on it and react to player feedback. They certainly don't need a sequal 3-4 years down the line.