For sure! Drakken especially is me, just drawing, not trying to make him any specific way. Trying to add some angles and realism, but not detract from the original design. I'm really glad you saw this, as I kept thinking of you when I was drawing Dr. D!
I tried to make her more mysterious, angular and push her away from Kim. Their designs are pretty divergent, but people tend to make them quite same-faced, where they are opposites. Shego has more triangles and sharp lines on her face and hair, then curves on her figure. Kim is sort of the opposite, in most ways. As far as coloring goes, I just put green on Shego, it was very fluid and quick. About twenty minutes while the rest took a half hour or more.