Of course if the option presented itself, people would prefer to play a stand alone DH class. The problem is in actual WoW itself, there's no space for such a class to exist, thus that option isn't really on the table.
It would be better to rephrase your question into this;
Would you be okay with Blizzard completely overhauling and revamping the Warlock class in order to bring a Demon Hunter class into the game?
That would be the more accurate scenario. See how many people on the Warlock forum support that one.