Yeah, Dan Savage is great. He's a some-time Real Time reporter on Bill Maher's show (as is the also-great Matt Taibbi from Rolling Stone). Bill sent him to a republican convention during the presidential election to cover it. Pretty funny stuff. (He's an openly gay man, in case that's not clear in his articles). He made some conservatives awfully uncomfortable with some hilarious questions.
As for your sister, just let her know subtly that you are not like your dad and open to people of other faiths, backgrounds, and sexual orientations. Then she will feel comfortable to talk about this if she needs to. I agree that it would have benefits, although there are also drawbacks. Still, another couple generations and most of the anti-gay bigots will be wiped out.