Hi Captain Chirri,
Not sure if you've had any luck, but was thinking you could always try the BSG fanfiction writers list, if you're coming up dry. Personally, I'm not familiar with Buffy, and am a few books behind on Harry Potter, but I read back to your pitch of your idea in May and it does sound intriguing. Starbuck and Harry, eh? I wouldn't mind seeing what you do with that. Maybe you could field that other group of BSG writers for a beta reader, as I don't think I'm the only one who took so long to find my way over here. If you're interested, here's a link:
http://lists.eyrie.org/mailman/listinfo/bsg-fanfic