Sacred Mesa gives you an extra engine for more, and Pegasus Refuge works well with the heavy drawpower this deck runs to make up for it's weak creature base, even if chucking a white card for a 1/1 flyer feels bad
These cards help you achieve the goal of winning or having fun
Cards with the incubate mechanic create an Incubator token, an artifact token with some number of +1/+1 counters on it that you spend mana to transform into a Phyrexian artifact creature
That means more creature tokens, more +1/+1 counters, more loyalty counters on planeswalkers as they enter, and more of whatever counter-based nonsense your deck has chosen as its profession

Grey Knight Paragon Hour of Reckoning Inquisitor Eisenhorn Inquisitor Greyfax Inquisitorial Rosette Knight Paladin Launch the Fleet Marneus Calgar Martial Coup Memorial to Glory Mind Stone Mortify Neyam Shai Murad Path of Ancestry Port Town Prairie Stream Primaris Chaplain Primaris Eliminator Reaver Titan Reconnaissance Mission Redemptor Dreadnought Sanguinary Priest Scoured Barrens Sicarian Infiltrator Sister Hospitaller Sister of Silence Sister Repentia Skullclamp Skycloud Expanse Sol Ring Space Marine Devastator Space Marine Scout Sunken Hollow Swords to Plowshares Talisman of Dominance Talisman of Hierarchy Talisman of Progress Terramorphic Expanse The Flesh Is Weak The Golden Throne Thunderhawk Gunship Thunderwolf Cavalry Tranquil Cove Triumph of Saint Katherine Ultramarines Honour Guard Utter End Vanguard Suppressor Vexilus Praetor Zephyrim NEXT: Magic: The Gathering Warhammer 40,000 Commander Deck Previews: The Ruinous Powers