kewms, out of over more than a dozen black belts (which oddly enough is half of our dojo) only one is female. She is older and has been out for the last year or so due to a combo knee/ back injury. I miss her, if in part because I got to watch someone who was barely 4 feet take down 6'5" men like they were nothing. In the short time with her, I had learned a lot.
One of the most intimidating people I know in aikido is a sempai of mine from my old dojo. Well under five feet, barely 100 pounds fully dressed, but a spirit two or three times that size. I want to be her when I grow up.