We enjoy the birds and butterflies that will call our land home. Your landscape should be humanized. This can be accomplished by running a woodchip or stone path through the yard, placing a bench to create a sitting area. Other human elements, like birdfeeders or birdbaths, are a good idea. I have even seen gazing globes used to create an interesting effect in the natural landscape.
Sundials are a nice touch.
I have a small windmill and old wagon wheel among my prairie plants. Such artifacts serve three purposes. Like the frame idea, people will accept that which they know is intentional as they will reject the same thing if it appears random. Second, such artifacts lend a sense of welcome to people. Natural landscapes are less threatening if they contain inviting human touches.