@Ovium Woah, and here I liked your art a lot and started examining it for things to learn.
To answer your questions, I do like to do a rough sketch layer, and then overlay another sketch layer that's slightly higher opacity that's a little more clean in another color, then I use the slightly cleaner sketch for working on lineart. Most final details I add in lineart, like the seamlines on her pants leg, her claws, and her scales.
For references, I typically look up the animal I'm basing the design on and draw a page full of heads from photo reference. Things like National Geographic and such provide some really nice photography, sometimes with very expressive creatures. It generally takes me at least one full page of heads (typically about a dozen experiments) to get down some of the major proportions in a way that I can apply to original work. Digitigrade legs took a while to understand, but I picked up from a source somewhere that the "extra joint" is more like the human ankle in terms of bone structure, so it helps to think of the animals as walking on the balls of their feet if they are digitigrade. Unguligrade is a step up and usually seen on say, horses, and that's like they're walking on their very tippy-tip toes. There are some animals (such as rabits) that are plantigrade, like humans.
Personally, I find anthro characters a little easier to work with because there's so much about their anatomy that you can exaggerate and work with, whereas with humans, proportions are far more rigid and solidly defined. The variety helps cover for a lot. Besides that, I have a bit of a weakness in drawing human elbows, so when I draw them in anthro, I just throw a tuft of fur there and it's totally fine.
Hope that helps a little, if you're ever interested in working on anthro character designs yourself.
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@Lego: yes. Much attitude. Her formal occupation is actually stripping, so I hope it carries well. What I'm probably going to do is lay down some quick flat colors and see if the face still bothers me. If it does, then I'll do some minor changes. I think the line width variety is what's getting me--and that it's hard to tell the volume of her face without some of those stripes to imply curves.