nirguNa in the vedAntic sense implies freedom from (or transcendence of) guNa-s rather than absence of guNa-s. nirguNa implies 'guNa mukta' rather than 'guNa rahita' - the freedom from guNa-s must necessarily include the freedom to take on any and all guNa-s.
Yes, that is Saguna. In the taittirIya upaniShad (II.vii), Nirguna brahman is described as 'aniruktam' - inexpressible. So that should shut all discussions about nirguna Brahman.