I wanted to respond to at least one of your two questions.

Question one: Yes, you can get mileage credit from Virgin Blue flights to VS FC. The VS website does not list this in the usual Airline Partners location but somewhere else on their site. Question two: Most likely not based on reading other posts.

On another note, I have been part of FC for a number of years yet I fly with VS probably once a year. Ironically, most of my miles go to VS because of my travel situation and preference but that's just me. (Last year, for example, I flew VS, NH and SQ, yet all the miles and points went to VS, which was rather hefty). I think it does not hurt to have VS FC just to give you flexibility in terms of mileage being available for use with an international carrier in case you need or want them someday. IMO, having VS FC and One Pass (SkyTeam) would be great.