Many people are stuck on the old fashioned Appy. Those are ugly for the most part, conformationally. Fortunately nowadays there are other breeds being bred into the appaloosa which is refining the look (or am I wrong?). That's just from what I've read. I've ridden plenty of Appys and loved them, but know little about the breeding side.
When I shop for a horse for my fiancee I would definitely look at a Paint, QH, or Appy for their level-headed-ness-ish-y.