IMO andrea's mod is the only one giving me impression like i'm actually on the real track, and not just driving a simulation.
Included just the best PP filters from my extended testing of the mod, i personally only use "AGI_Internal_Low_G5"
Due to multiple requests i've made a multiplayer compatible version as well, that will replace the default 7 weather files.
1. Unpack the "AGI 1.4 + MP compatible.zip" into your main AC folder (steam/steamapps/common/assettocorsa), (Make backup of the original files if you want)
2. Unpack "AGI 1.4 MP compatible.zip", if you want the mod to be online compatible (i have handpicked the best 7 weather files to replace the default ones)
2a. Or unpack "AGI 1.4.zip" if you want to have all of the weather files.
3. Put saturation in the game to 100%
If you're having trouble loading the tracks, do a Steam integrity check of AC, and then unpack and replace all files again.
My personal best choices are "Light Clouds" (a.k.a. Covered A), "Clear" (a.k.a Clear Summer AGI), "Mid Clear" (a.k.a Cloudy Spring AGI), in combination with "AGI_Internal_Low_G5" filter.
Some image examples: