My own spin on Rainbow Dash (Second sprite, constructive criticism please!)

[Gors]

this being said, steer away from stylised representations of the objects, observe REAL nature (you know, animals that aren't rainbow-colored with anime hair and eyes) and try drawing it as realistic as you can, respecting all anatomy and details. Animals are indeed a very difficult subject to master and making shortcuts like this will simply not work.

After you're comfortable with the anatomically correct drawings, then you can try stylising it. This way you'll have a cartoony animal with the key structures that will make it look like that animal.