Great news rubberduck
Right, Normal mode is the better one.
I liked the wet asphalt more. Although, from my experience and my reference in Richard Burns Rally, they have even a stiffer asphalt. Makes it more difficult in those narrow stages. But the VDrift circuts are quite broad, way too much for rally.
This is actually prepared to be changed. There are few tire presets (asphalt is definitely a one, even wet asphalt is another). So changing it doesn't effect other.
Rest is set in data/carsim/normal/surfaces.cfg (bumps, friction coefficient).
There is even an in-game tire editor (which is used to make presets and save .tire files) but that's something very complicated to tweak.
And making another simulation mode is also possible, but easier is to just edit normal or easy.
I intend to someday make Hard (realistic) simulation, but for now, I still can't set the tires to what I want. And need to make the suspension less stiff (when stunts aren't present on track).