Mmm.. I think you should at least mention a reference to "uncharted waters" but anyways the faces are nice. You could minimize a bit the females face's rough lines as in the nose and cheekbones so they look more feminine and as said in the dog and cat animations try to avoid putting the legs in the same places so they are preceived as movement.
the mini faces are great, they really read well.
That cat's face is terrifying in the portrait. It's staring into my soul.
There is nothing much animation to be done in 2 frames and small size pixel art, pretty wel done with the limitations...! 
Cat's and dog's walk animations are strange, but overall it's a pretty good work.
The faces are the best part, I'm so jealous of how simple yet detailed you made it!