I love both names, especially
Rudolph, which is definitely usable. I love
Rudy and
Lottie as nicknames, and although
Lottie could work as a full name, I don't like it as such.
Alternative full names for
Lottie (some more obvious than others):
Lieselotte /
Liselotte,
Carlotta, Annelot,
Letitia,
Atalanta,
Ludovica,
Loredana,
Clotilda /
Clotilde,
Ottilia /
Ottoline, Leopoldina /
Leopoldine...