I like it only as a nn for
Gabriella. It sounds incomplete and nny as a full fn to me.
Also,
Gabriella offers your child at least two more name options to go by (
Gabriella and
Gabby) than a Briella has (Briella, Brie,
Ella, and
Elle).
Miranda

Proud adopter of 15 punctuation marks; see my profile for their names.