[Opinions] Re: Nickname help
Allegra: Ara? A bit of a stretch... The only things that are coming to mind are sort of ugly sounding (like Leggie and Eggie :P) Personally I think Allegra is short enough to not need a nickname, but everyone has a different length threshold where they start to shorten names.
Calista: Lisa, Lista, Listi, Calla, Calis
Juliet: Jul, Li/Lee... Liet?
Sapphira: Sapphy, Sappho (although that's an entirely different full name), Phira, Fira, Saffy, Sira, Saphha, Saffa? If I had a Sapphira I'd probably shorten it to Sapphy or Saffy or something like that. Maybe Phira/Fira. (I like the sound of Phira but not the PH spelling, and it might be weird to use an F when there's no F in the full name.)
Valentina: V, Vina, Vala? I actually like just V as a nickname.
Seraphina: Phina/Fina, Sina (I used to know a Christina who went by Cina, pronounced like Sina), Serina