I personally didn't like the first movie too much, but it was because I couldn't really get into the story all that much; not because of the stereotyping. Plus, from what I remember, it mainly only focused in one area and we only saw a small collection of cats and dogs. It could be that not all the cats were evil; just the ones we saw. And there are likely some evil dogs too, again we just don't see them.
To be honest, I found the concept to be interesting, at least when I saw the trailer. The idea of the two species not only just not getting along, but actually waging war against each other, was a unique concept, in my opinion, and was the reason for me seeing the movie in the first place, though it still disappointed me in the end.
As for cats being good and dogs being evil, I'm sure there was some story that was written that depicts this. I wouldn't really be surprised anyway. The closest thing I remember seeing to this is the movie Oliver and Company, where the main character is a kitten who was left abandoned I believe, and two of the main villains in the movie are dogs. It's not quite the same since there are good dogs in the movie that take in the kitten temporarily. And Oliver is the only cat character in the movie, I think.
