I would prefer to have a date estimating what time period the particular creation story was created.
One thing to remember is that most of the Egyptian creation stories aren't in a nice, neat source. In many cases, they're pieced together from funerary texts, magico-religious sources (spells would link the magician to a similar mythological act), and even 'mythogical manuals' like the Tebtunis and Delta books, which give many different versions of the same story, with different deities and variant actions.
Given that, we have the Heliopolitan cycle, which has Atum precipitating him/herself out of the formless Nuun, being bored because there wasn't anything else, masturbating, and bringing forth Shu and Tefnut. Shu and Tefnut have Geb and Nut as children, and Geb and Nut have the famous siblings Osiris, Isis, Nephthys (Nebt-Het), Set, and (sometimes another form of Horus-who-wasn't-a-child-of-Isis). There are also texts about the gods being made from the sweat of Atum (etc) and humans, male and female, produced from his tears.
There's the Memphis cycle, which involves Ptah using speech to bring about the universe. There are a lot of variations of this. A version is also preserved on the Shabaka Stone in the British Museum. Shabaka, one of the Nubian pharaohs, (25th Dynasty) ordered it made based on a 'worm-eaten papyrus'. Unfortunately, the stone was turned into a millstone at some point, with a hole punched in the center.
The Hermopolitan story involves the Ogdoad- 4 male frog gods and 4 female snake goddesses, who cause the primal bit of land to emerge from the Nuun.
Amun, who was one of the Ogdoad also has a creation story centered around him.
Other stories include Geb being in the form of a goose and laying a cosmic egg on the primal mound of land. One about Ra emerging from the bud of the first water lily (there's a statue from Tut's tomb that references this). And the goddess Neith (Nit, Net) created the world by differentiating the land from the waters, again from the undifferentiated Nuun. In some versions, the goddess Mehet-Weret 'Great Flood' is involved with Neith's story.
Sometimes more than one of these cycles is mentioned in the same text, so they weren't always exclusive of each other.