...Phyllis Diana? My mama has an acquaintance by this name, and I used to have a massive platonic crush on her.
Anyway, to answer the question myself, I LOVE Phyllis, but I think it clashes with Diana, which is a name I've never liked. That said, the combo is okay overall, though mostly because it's my former platonic crush's name. I'd consider naming my daughter Phyllis, but not Phyllis Diana.
~Verne~