I like
Theodora, but not
Teddy. I don't usually like unisex nns, though.
My favorite nn is
Thea. I don't know if
Theodora is pretentious or not, but never care about that.
I really like
Mariah (spelled
Maria),
Philip,
Alistair, and
Alec (as a nn for
Alexander). I've always thought
Alec sounded much nicer than
Alex.