Grass/Tree - Density/Distance ingame graphics options
Grass and trees are pretty hard on computers. I think it would be good to have ingame graphics settings that would let you control the density and distance of the grass. Overall tree distance and the distance at which billboards are used.
If we had ingame settings modders would be free to do whatever they want and not have to up upload multiple versions for compatibility. People could tune the settings for their system.