The comment :- "too much green for my tastes!",
Well, it IS the green hell


.
Have you tried driving the track at a time other than noon? Just a changing of time of day has great affect on the saturation of the colours.
I see in video there are no clouds. Try changing the weather from Clear to Overcast and you will see a big difference. I made screen shots 12:30pm, each one with different cloud settings.
Clear

Mostly cloudy

Overcast
Rfactor does add lots of saturation at this time of day as it's trying to make the track look sunny.
There is danger here, we go lowering the saturation on trees, then the grass looks over saturated. Then we change the grass, then the bushes look bad. After changing the bushes, then you find other things that looked fine before are now all out of balance, kerbs, people, tents, even the cars on the track can then look too bright or over colourful. There is big danger of making the track worse. Think there was one early version that Pleclair made that ended up the wrong way like this. So do try overcast or different time of day and report back.
Same story with the Force feed back I guess. We make all track with no feel, and that makes you change your force feed back settings to a lot higher settings with lower filters, then you hit a kerb and boom your wheel jumps off the desk
DJC