Grand Arbiter decks tend to play more as stax than as pillow fort, by the simple virtue that youre already messing with your opponents game plans
Space Marine Devastator, Grey Knight Paragon, Sister of Silence, Callidus Assassin, Swords to Plowshares, Collective Effort, Mortify, Deny the Witch, Entrapment Maneuver, Utter End, Birth of the Imperium, Primaris Eliminator 12 targeted removal
Most casual players are willing to trade a couple of exiled cards from their library to add another land to their fat stack, and you net cards quite often
That price
Mono-red players maximize the abilities on Inti, Seneschal of the Sun because you follow up your turn-1 play with Inti, and attack with the buffed 1-drop
What do you hope to see from populate in the future