Here's my labored rough line drawing, done in Photoshop with the rest of the process.
Then I block in my values. I like using the Pyle style process with a violet hue; mainly because that's how I traditionally learned how to illustrate.
Then...PAINT! You can probably notice some of the line drawing in the painting. Sometimes I don't bother trying to replicate the line that I made. It's just easier to use what I already have. I'm a better draftsman than a painter anyways :)