I made the eye markings tribal and rainbow and I added a smaller tribal mark on his/her hip. I saw you liked some more natural patterns as well, so I hope that this is okay.
Ref used loosely for eyes: http://4.bp.blogspot.com/_ZD0UIcP-AxU/T ... 00/CTM.jpg
PS - I left this window open and walked away.... Please ignore the timer entirely.
Edit - I forgot to color the paws on the side xD