secret drawings of a roller girl

Starting to put my "book" (for want of a better word) of illustrations together. Thought maybe I should have more interesting cover art.. or maybe I'll put this on the title page inside.. hmmm decisions decisions...
(photoshop sketch and pen and ink drawing)

roller derby doodles..

Any roller derby people will have to let me know if these make sense/ are any good. 

I've been thinking I want to make a book of these kind of really quick drawings. or something.