I'd say create what you truly feel you'd enjoy creating the most and roleplaying, if that's what you'd like to do. Whenever I'm going through the same thought process, I like to look at a list of different canines/felines and seeing what I could interpret into my own character; what I haven't seen running around often or at all are: Jackals, Dingos, Dholes, Raccoon Dogs, Caracals, and Mountain Lions/Cougars.