+1 to restricting canon characters with no changes at all. After hearing some other's thoughts, I think I'm decidedly neutral on this. As long as they have permission for any images etc they're using, I don't really care if people keep a folder of the canon characters they RP or have links to or something like that.
-1 to everything else. It's strange to me that so many people seem to be against "canon character as a dog" but okay with characters of a canon species. What makes a purple Pikachu more "original" than a dog whose design is based on Ash Ketchum? There's so many different ways to adapt the design of a canon character onto a different species, and many of these interpretations can be quite creative. In some cases you may not even be able to tell who the character was based off of unless the artist told you. I'd rather neither be banned of course, but if we're basing this on the argument of canon character based designs impeding on the copyright holder's IP, then it would be hypocritical to say that they should be banned while alternate colors/designs of canon species should be allowed. However, the first post of this thread seems to suggest that this is being brought up because people are tired of seeing fandom OCs. If that's the case, then I'm sorry, but no. Everyone has their own way of enjoying characters and I can't agree with the banning of any sort of character simply because some people don't enjoy certain types of characters. If it's really that big of an issue, make a fan character checkbox/ filter so people don't have to see them if they don't want to. But outright banning them for that reason is absolutely not the way to go.