Maddigan seems like just another weird masculine surname being used on a girl, which is actually one of the heights of tryndeeness right now.
I would go for:
Madaia (see
Madai)
MadalenaMadalinaMadaraMaddalenaMadeleineMadelinaMargaret (cf.
Madge)
Miranda

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