I could definitely be interested in something like this, assuming we won't be limited to household pets? 
I'm thinking more along the lines of bears and lions rather than unicorns and dragons (Things you could come across at the zoo).

Just to be clear though, how old can the characters be? 
I saw that characters get moved to the training facility at 15 (and I'm assuming that's where the characters will be). But is there a limit on how much older a character is? Or should they all be in their teens?