My nemesis: natural-looking, rolling hills

[Greason Wolfe]

Mr. D has the right of it, only two or three hills at a time will probably help. Also, if I read your post correctly, once you start putting in the forests (and possibly grasslands?) you might find that things start looking/feeling a bit better or more complete.

Another thing that might help is more variation of the hill footprints (read that as width) and less aggressive sloping (read that as height) particularly in areas that are "slow rolling." Try to think of it as the surface of a large lake or ocean. Some waves are large and choppy, slamming a boat all over the place while others flow along rather smoothly, rocking the boat gently. And don't be afraid to break up (or put holes) in your forested areas with a hill or two every now and then. That will give it a more natural feel.