I think Delphine is a really interesting name (in a good name) I think it's easy to pronounce, sounds beautiful and it's not common.
Prefer Delphine over Delphina and Delphia as it's easier to pronounce and flows better to me
*~Loads of Randomness~*
My PNLs:
http://www.behindthename.com/pnl/150423