Currently, sites won't allow for any names with a space, hyphen, or in them. I believe it would be a good and popular idea to include some basic character (punctuation) options. These do occur in real life, so why not bring it to the sites? (Take the names Keegan-White, O'Halleran, Gracie Jo, and so on)
Of course, the system with it can't be perfect, but incorporating a one-special-character-per-box method might be in order, possibly having to use a number of "regular" characters in addition.
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