I agree with topic starter weezzah on the lightning being far too washed out when looking outside from the cabine. I found out that setting the lighting quality to "very low" there is no washing out anymore but the overall quality of the cabine gets worse also.
A human eye can do better in difficult lightning situations then most camera can. Try to make a picture with a camera through a window from inside a house where you can see inside and outside the house: the camera struggles greatly getting the lightning both inside and outside right. The human eye does much better. Thats why HDR has been invented to overcome this problem.
Simrail lightning reacts more like a digital camera, and imo that's not the way it should be.
I think the developers should tweak these lightning settings, f.i. in a way a user can set this to his/her liking.