We are thinking about the same thing. I went for a ride today and saw a rose covered with some nice hips and made a note of that. My foundation will be conifers and other ever greens which I have in my own yard or see in neighbors yards. They don't begrudge me a little judicious pruning. My Son has a nice Holly in his yard and I will use some of it. Perhaps I can find some green and white holly. Then I will look for berried branches, rose hips, crab apples, Hawthorne.or even pyracanthia. I like Mahonia,,Oregon Grape...especially if it has taken on that red bronze color. You can preserve Oregon grape by putting it in 50/50 anti-freeze and water. It takes on a leathery look. I also like a few bare twigs....Go for it....anyone can develope a creative eye if they try.