Great list! I think this sort of list is a better approach than trying to compile a list of stand-alone SFF book—where everyone pleads for exemption status for their favorite almost-a-standalone-if-you-look-at-it-from-this-angle non-standalone books.
SFF Authors. No sequels. No revisited characters/universes. No exceptions. Who are they? (authors with only 1 book published don't count).