Dack Fayden is terrible sadly enough. His +1 is great but both his other abilities are shit.
As for Teysa 2 (or Tits McGee as my playgroup calls her), she's too slow to be a good commander, but my playgroup is incredibly casual so she works pretty well. I run all 15 extort cards and a LOT of pillowforting, and Teysa is basically a No Mercy you don't have to tutor.
Athreos is the only card in JOU that is good in competitive MtG but not in EDH. Paying 3 life is nothing if you start with 40 so you;d have to politics bro-op to make him worthwhile. I've seen Modern Affinity players playtest him which, albeit slow, is downright sadistic; "I sac 2 thopters, a Memnite and a Signal Pest to my Ravager, then sac the ravager to pump my Vault Skirge. Pay 15 life or shall I do it all again next turn?"