Lumping the Kaladesh mistakes with the current ones is a bit dicey
A well-centered card will have equal borders on all sides, and thats what PSA wants to see
Natural EmergenceNatural Emergence is the best of the lot, since its a constant static ability, which then makes cards like Soul of the HarvestSoul of the Harvest strong

Abuna Acolyte Adorable Kitten Adorned Pouncer Aetherstream Leopard Ajani's Chosen Ajani's Pridemate Ajani's Sunstriker Ajani, Nacatl Pariah Alacrian Jaguar Alms Collector Angelic Cub Arahbo, Roar of the World Arahbo, the First Fang Arcbound Mouser Arcbound Shikari Arcbound Slasher Arctic Nishoba Armored Guardian Armored Skyhunter Balan, Wandering Knight Bane-Marked Leonin Basri's Acolyte Bast, Panther Goddess Black Cat Black Market Tycoon Blade of the Sixth Pride Blistering Firecat Bola Slinger Bounding Felidar Brimaz, Blight of Oreskos Brimaz, King of Oreskos Brokers Initiate Bronzehide Lion Cait Sith, Fortune Teller Canopy Stalker Canyon Wildcat Cat Warriors Cat-Owl Cauldron Familiar Cave Tiger Chandra's Embercat Charmed Stray Chartooth Cougar Chrome Cat Chrome Prowler Civil Servant Coeurl Crazed Firecat Cruel Caracals Cubwarden Dawnwing Marshal Denry Klin, Editor in Chief Diamond Lion Displacer Beast Displacer Kitten Dreadmalkin Eager Glyphmage Elite Cat Warrior Emeritus of Truce Enduring Curiosity Enlightened Ascetic Entrails Feaster Envoy of Okinec Ahau Falthis, Shadowcat Familiar Felidar Cub Felidar Guardian Felidar Savior Felidar Sovereign Feline Sovereign Feral Maaka Feral Prowler Ferocious Tigorilla

A 2 mana 2/2 creature that can be played in response to a fetchland like Wooded Foothills, a watered down version like Fabled Passage or Terramorphic Expanse, a ramp spell like Three Visits, or another means of cheating cards into play like Kodama of the East Tree in order to ramp out one Plains card from your deck is already good value