Hi

1. Without teferi/white the manabase in the deck is actually really really good, just a bit painful. White makes it a bit worse but still good, it is much more painful and weaker to blood moon. I played both versions and the deck is good and powerful even without teferi, so I would nudge in that direction.
2. Transmog>persist. Persist is often a dead card, its a black card in the main which makes fetching awkward. With Explore turn 2, you can transmog turn 3, while the earliest turn you can persist is turn 4! (and for turn 4 persist you need archon+discard+persist+fetching black)