Ayli, Eternal Pilgrim: Ayli is an interesting card for this deck. Using it first for its value as a 2/3 deathtouch at 2CC spot. It's first activated ability plays into the lifegain/drain focus of deck, can be used to sac blocked/blocking creatures, has synergy with
Zulaport Cutthroat and
Stone Haven Outfitter. Additionally despite not being an ally it shares a type with all creatures (either kor/cleric) except
Drana, Liberator of Malakir and
Zulaport Cutthroat. Therefore, equipping a
Stoneforge Masterwork could be a very solid play as could easily be a 4/5 or 5/6 deathtouch.
Kalastria Healer: Great 2CC ally, great early drop. Synergizes with most of the deck generating drain/heal which principally helps fuel Serene Steward. Works great with new Captain's Claws and Gideon, Ally of Zendikar token generators
Stoneforge Acolyte
: Recent addition, trying out. Allows use of fewer equipment and/or greater chance of accessing one in first few turns. Best as first turn drop. Several 2CC creatures are not intended to attack mainly so works well with acolyte as a turn 2 play.
Stone Haven Outfitter: Another recent addition. While the +1/+1 is likely to be better in a R/W Boros ally equipment deck, we can try to take advantage of secondary ability more. This has great synergy with Captain's Claws and Ayli, Eternal Pilgrim. Former is easy to re-equip and generates tokens and latter can use to sacrifice equipped creature intentionally (and gain 1 more life from the +1/+1)
Drana's Emissary: Card I've always liked, a solid 3CC creature. Has evasion with flying which works well with the aggressive Captain's Claws and can life/drain and play defense. Great synergy with Serene Stewart
Drana, Liberator of Malakir: Best creature pound for pound in the deck. If not blocked/removed (especially with an attached Captain's Claws) can get out of control quickly. Also due to its first strike if it hits player it will add the +1/+1 tokens to others attackers before they do/receive damage. Pushes a more aggressive style, but is a lightning rod and high chance of being removed.