Catastrophe can be useful in a midrange or control deck when ahead or behind whereas kirtar's wrath is only good in control.

Centaur chieftain's threshold ability is quite inconsistent and I feel brawn will end up getting more damage through over the course of a game.

Oath of Druids is an interesting build around that only costs one slot. I primarily see this in a deck but and both have big creatures that could be worth cheating into play. Harrow plays a similar role to yavimaya grangers but harrow fits into this oath deck better.

Jolrael's ability has too big of a cost so she is being replaced with a more efficient legend that can fit in all midrange decks: Mirri.

Kor haven is another boost to the legends-matters deck that I had previously overlooked.

Oath of Ghouls and krovikan horrors give the hand recursion aspect of black a bit more consistency.

Keldon firebombers stops your opponent getting to enough mana where they start outclassing your swarm of threats. I am expecting it to be particularly good against control as it can keep the deck of board-wipe mana.