I've only known one
Adelia who was always called
Dee. Also, where
Adelia seems over the top to me,
Delia is just perfect. I prefer the three-syllable pronunciation.
Delia Christine is my favorite of your combos. Other mns:
Delia CorinneDelia CatherineDelia CharlotteDelia ClaireDelia CarolineDelia FrancesDelia Margaret (love this one)
Delia PenelopeDelia RachelDelia Susanna,
Delia SusanneDelia Victoria