To be fair, Winters is ~ 5 miles from "foothills" that have enough elevation to make it interesting for retirees. Running down Pleasants Valley Rd will yield Cantelow Rd, Mix Cyn and Gates Cyn Rds. If the latter two don't get your attention as a climber, then perhaps the flatlands are a better choice. Heading due west is Lake Berryessa and Napa County, which is not pan flat like Yolo County.

I wouldn't have thought of Winters as a retirement option, but, since it was mentioned I suppose it would appeal to certain retirees.