We had a discussion about this topic recently, but I can't find the thread.
My take...Let the catcher's skills on the field determine whether they are a good choice behind the plate, regardless of which hand they throw with.
I searched before posting this and it seemed most if not all centered exclusively on softball... While I agree that skills and ability should be the determining factor, I can tell you that baseball and softball are different animals not just in the way the game is played but in the way it is coached for the most part unfortunately...