Hmmmm. Well, I don't really favor one over the other. They're both pretty much equal when it comes to my preference.
I guess I'd pick
Hannah
Madeline is decent and nice but I don't care for the presumably unavoidable nn '
Maddy' and any 'mad' prefix name unfortunately reminds me way too much of '
Madison' a name I cannot stand. I prefer to say
Madeline with the 'line' ending.
Madeline or
Madeleine. I'd say it with the lyn\lynn ending if it was spelled as
Madelyn or whatever