Wow - 100 is too many!
I did 50 last time and also ended up crunching at the end. If they do another series I think my limit will be 25. So many people are really busting out major efforts on these cards that I think it's becoming more about testosterone and competition between artists than just giving a quick little sketch bonus to cards buyers.
Next time -- each one an original oil painting with applied gold leaf for effect!
Or not. Maybe just colour.