I'm really loving those forests. I think I"m steal them if I ever so an atlas styled world or regional map. I think what will make your mountains look better is more "branches or roots", indications of elevation in the forest due to tree lines not being at the base, I'm a fan of snow caps not sure if thats the type of elevation your going for but it could help, also I like seeing some mountain ranges with several peaks in bunches either with forested valleys or non. Hope that helps, unsure on how you will accomplish it since I have yet to really branch away from smaller scaled maps personally.