I put The Frenzy down today in a 1 commander game, Relics of Ancient Malifaux and Sharktooth Necklaces.
While it was nice being able to cast 3 Healing Magics, the bonus flips to Actions are a massive, massive bonus from Sharktooth Necklaces. They did so much heavy lifting, since you really want Crows and preferably high cards on their melee attacks. They managed to kill the Lord of Steel with all their bonus attacks brute forcing through Evasive Maneuvers.
It was a real shift from the Stormsirens long range luring into tide pools so I was initially hesitant to try them single commander, but I'm glad I did.