I read Candide by accident when I was 15 years old at my local library. And I too did not understand first what Professor Pangloss was suppose to be, and then later discovered that he may have been a cariacuture Liebnitz, or just a personification of the principle of the Liebnitz's Optimism as you have said. I can't be sure on that. And about Voltaire, maybe he was only exercising his ability to write a parody about something that was probably in fashion in Paris during his time, or was it just an act of his usual contempt toward German-speaking people in general? Which I may add that he was not shy of showing it in his other works.