#9: Have you ever played a character of the opposite sex. Why or why not? If yes, how did the other players react?
As a GM, of course I have! But I'm guessing that's not really what this question is about.
In 27 years of gaming, I have never seen anyone effectively play a character of the opposite sex. In every case I've seen, these characters end up being more caricature than anything else. I can tell you it's an area of discomfort for me as a GM (I never feel like I do women justice when I play them). When you're dealing with a game table that includes people of both sexes, people can get downright offensive. I don't completely disallow cross-gender play at my table, but I do discourage it. And when someone chooses to go that route, they're put on notice they may be asked to change.
Obviously this strong opinion is based solely on my experience. I'm sure it's been done well, somewhere. And I'd love to see it.