To me things like genetics, maintenance, breed history, and size would be the most important. I probably already know about the appearance and colors and such just aren't that important. I mean a brown dog will work in my household just as well as a black dog, but a 100 # dog won't, and many breeds have different sizes within it. (Some people wouldn’t know that there are standards, miniatures, and toys of certain breeds, or the size differences in males & females.) A dog with it's origins in Africa doesn't affect me as much as a dog with a genetic tendency towards cancer or wobblers.