@Braxton first I really like how you are using value and value contrast to provide focus on the main characters.
But I feel like they seem a bit cramped. I wonder how it would feel if you gave them more room to breathe. I would agree with @Brad-Newman that the animals are all about the same size and if you varied size some more you might be able to free up some of the dark space.
You might try lighting some of the bottom area where there isn't an animal on the left and then put dark text on the lighter area instead of having light text on the dark area like it is now.
Just some thoughts.