I've done a little cartooning and I know that it is much harder to do than one might think. For it to be believable, you do have to a
Have some understanding of anatomy, and pay care to be sure that the subjects are positioned over their center of gravity, as they would in real life. If not, they
Will look as if they are about to fall over to one side. I don't know why, but this is always hard for me.
And getting the facial expression is the key, and so easy to get wrong.
Have you taken classes in cartooning, or just learned it on your own?