Help with lighting general and trees

Hi there

I am hoping somebody here will be able to help me. I have pulled together a very basic level and I am trying to get the lighting better as well as the look of the trees. I have a couple of questions.

  1. In the image below, the billboards are appearing too soon, as you can see in the distance. Is there an easy way to get it fixed. I have looked at the docs and have played with the settings but I am just not able to get the results I am after.

  1. The light on the horizon seems quite stark, I have tried moving the sun, changing time of day and adding atmospheric fog but none of these are giving me the look I am trying to achieve. Could part of the reason be that I have quite empty space?

  1. Lastly the needles on the trees. I have used SpeedTree to create the trees, but I am having problems getting the needles to look realistic. I think it may have something to do with the material setup, but then again it may just be the lighting. Any advise?

  1. Lastly, any general feedback on improvements in so far a lighting would be greatly appreciated. I am using a postprocessingvolume with colour grading applied. Are there any tips you can share for improvement?

Many thanks