Storybook Practice Drawings

My assignment was to draw/sketch five different characters.  I'm not really proud of any of  these, but I had a choice.  Draw what came to mind or sit around waiting for something brilliant (a.k.a. not drawing at all).   Perhaps a detail from one of these will push me in the direction to something better.

Bee Alligator:
What's good:  I like the flowers.
What's bad:  I don't like anything else.

Butterfly with Mangled Wings:
What's good:  I like his expression.
What's bad:  Too depressing for a children's book.

Cat and Dog:
What's good:  I like their personalities- you can tell they're up to something.
What's bad:  Cat and dog?  Like that hasn't been done a zillion times before...  Also I don't like how the background is washed out.  I would have made it more colorful, but feared it would be distracting.  I wish there was a book called "How to make engaging cartoon backgrounds that don't 'fight' with what's in the foreground."

Dragon in Dungeon Nailed to the Wall.
What's good:  I like the frowny face window.  Also the character seems sympathetic.
What's bad:  Too warped and depressing for a children's book.

Weasel and Basilisk
What's good:  I "painted" them with a texture of a pear my friend posted on facebook.  I think it makes the sketch more interesting.
What's bad:  Background is too sparse!  I wanted to add more detail, but didn't know how to do so without  interfering with the foreground.  I also should have left out upper joint on Basilisk leg.  And why doesn't he have eyebrows?