Maybe some more barks, yips, meows, purrs... Stances such as fighting stances and such, maybe grooming, nuzzling, and add a yawn expression with the Stretch action.
If anything more noises would be fun, much more fun for communication since some cats don't roar [such as the cheetah] and others don't meow [like the serval]
If anything, I love the idea of new actions. Maybe a tail swishing/wagging animation you can turn on and off? -dunno-