I really love Kristin Cronin-Barrow's nature-inspired kits and you could pull together a very greenery-heavy look that way.
That being said, I hope a designer sees this and decides to make a Hobbit/LOTR kit but I think embracing the theme would be so so so magical. I know I would buy it.
(If we are ever in a position to build our own home, my husband and I want to build a sort of Hobbit hole that we would call Underhill Manor. We can't go underground here at 6 ft above the water table but we could totally have a living roof with a ladder to get up, a porch swing, and a little concrete pad to put my tripod on for stargazing.)