I can picture
Billie in sort of a glamorous 30s way. For me it's hard to tear myself away from my association with my aunt... since she's the only one I've ever known, and it's her full name, not a nn. Not sure what her mn is though.
So let's see...
Billie EvelynBillie JosephineBillie EloiseBillie FernBillie FrancineBillie PearlBillie ViolaBillie MyrtieBillie BarbaraBillie MargueriteBillie MaxineBillie June?
It's hard to make a combo that makes me think of sequins and the 30s without sounding like an old lady.