You might also consider the weigela, Elizabeth. They can be hardy up to zone 3. My dad has one in his yard in rural Ottawa, Canada, which straddles zones 4 and 5. It gets full sun but primarily eastern exposure. There are a number of really beautiful varieties. Check out Carnaval, French Lace, Midnight Wine (my fave), Minuet, Pink Delight, Red Prince and Ruby Queen, which are all hardy in zone 5. There are also some Japonica and Florida varieties.