Very sweet lighting Frank
I am wondering: if you look at the striking light on the grasses to the right and compare that with the striking light on the grasses on the left; there's a clear difference in strength and saturation of the lighting colour. It looks like there's more glow on the right section.
Logically, as in TG2 the glow/glow power settings enable you to control the falloff of the atmospheric glow.
So my question is: is this difference I observe due to these glow settings or something else? In my opinion the lighting strength and colour saturation should be the same, hence the scale of the scene (it's not continental scale we're looking at).
My guess is that you can influence this with the atmosphere node, but can't get it as I think it should be. The problem is similar to getting highlights in snow or water to be present throughout a whole image, instead of only near the sun.
I think this is quite an issue with TG2, that you can't control this completely (at all). See this blenderguru tutorial which shows how you can "force" highlights" throughout a scene:
http://www.blenderguru.com/let-it-snow/ This is what TG2 needs IMO.
Cheers,
Martin