Since I would assume most of the drawings would be portraits I could probably knock them out in 5-10 minutes. Maybe even faster once I get comfortable with a pen. Although shading can drastically add time to it, if that necessary.
A possible problem is that I notice every flaw in the face and will portray that. I did an experiment on myspace where I offered to draw 50 peoples portraits to a certain degree of finish. I got about 11 of them semi-done before life caught up with me.

I'd like to finish that someday. Anyway one of the women I drew had some self esteem issues and forced me to draw her even thinner than she was. Even taken her face down to almost skeletal levels, she still wasn't satisfied. I realize you can't please everybody, but if its 60-80% of the people your still good.
Anime is tricky, similar to cartooning, although they pushed me away from it most of college since its not good for portfolio work.