The second question is a little more specific. I need the name of a musical that
a) Could feasibly, at some point, be on Broadway.
b) Has a key, challenging role that is suited for whatever the answer to question #1 is.
c) Also has an important role that would be suitable for a male singer with a very high voice, namely Chris Colfer (more links). It's okay if this would require some alterations to the script, like re-imagining an interclass or interracial couple as a homosexual couple, as long as the change is one that would be considered plausible for a daring director.
Third question: What are the odds that a piece of mail sent to a Broadway singer would actually be seen by said singer if it were sent by public channels? Could a semi-estranged family member increase those odds if she didn't know any kind of personal address?
What I've searched: Wikipedia's entries on both singers, the fan-made Glee wiki's articles on both characters, various combinations of 'Lea Michele, vocal range, alto, soprano, mezzo-soprano, great mezzo-soprano roles.'
(Yes, this is for a Glee fanfic. So for a setting, the U.S.A., sixteen to eighteen years in the future.)