Picking a color combination for the exterior is absolute murder.
After more great advice from Stephanie, I went to the drug store, printed out a picture of my house's exterior, made 20 photocopies, and began coloring with some colored pencils. I obsessed for a couple of hours and now have about 11 different color combinations. Most of them are horrible. The one that looks best to me is bone white with mahogany trim. It makes the house look a bit like an old train depot, which I like.
At first I was sure that I wanted white trim, but now I'm all over the place. After deciding to abandon white trim, I happened to drive past a bungalow with suede-colored paint on the wood siding and white trim. It looked so good, so now I'm sort of back to that. Arg!
I never imagined that I'd be the sort of person who subscribes to the Better Homes and Gardens website, but they have this great Java tool there that allows you to color in the exterior of a variety of different houses. They had one just like mine, only with much better landscaping.
Check it out. Honestly, it just left me more confused, but at least I can visualize things a bit better.