Bello, Bard of the Brambles is a great commander, and the secondary commander Wildsear, Scouring Maw is great too if you want to shift to a more enchantment focus as opposed to straight combat
Humans and cycling were two great examples of previous mechanics that let you use old and new cards
More cards are yet to be revealed, but this Secret Lair will be live on August 17
That puts this into a very different place, although you can still run it like a normal Fog by chump blocking and then keeping your chumpers alive
If you want to include Atraxa, Grand Unifier, just make sure your deck has a wide variety of card types, and that your color identity can support it, of course
Maybe: "Destroy target creature