Nice big cat! I was trying to doodle some the other day and I can already tell its going to take me a lot of practice to get the forms right. Those kitties aren't easy haha.
Something that's been helping me immensely is trying to build forms out of basic shapes. Your chimera looks great. I think some of the forms get a bit lost though. I hope you don't mind but I did a little paint over to show you what I'm talking about. 
Making a separate layer for volume lines keeps me from taking guesses when I get to the shading stage (which I am prone to do)
Anynoodle, hope this helps and great work!
