Cards like Angelic Intervention only give temporary protection, and others like Argentum Masticore has protection from narrow subsets of cards
Then, I can blink the planeswalker so I have two copies of the same card
Using these kinds of dual purpose cards will allow you to increase certain interactive and disruptive components of your build without hitting the engine consistency

Adventurer's Airship Archive Haunt Artful Looter Assassin Gauntlet Atlantean Skirmisher Bag of Holding Baron Strucker, HYDRA Overlord Benthic Biomancer Boosted Sloop Cait, Cage Brawler Carlo, Suave Schemer Chakra Meditation Copycrook Coralhelm Chronicler Currency Converter Customs Depot Cyclonus, the Saboteur Diviner of Fates Doc Ock's Henchmen Doctor Doom, King of Latveria Dreadwing Scavenger Emet-Selch, Unsundered Frontline Sage Furtive Courier Goben, Gene-Splice Savant Gran-Gran Illuminator Virtuoso Improbable Alliance Inspired Sprite Jace Reawakened Jace, Cunning Castaway Kaito Shizuki Kaito, Cunning Infiltrator Kamiz, Obscura Oculus Kang, Temporal Tyrant Kitsa, Otterball Elite Ledger Shredder Locke Cole Looter il-Kor Madame Masque Malcolm, Alluring Scoundrel Mary Read and Anne Bonny Mechan Navigator Mirrodin Besieged Muse Seeker Ninja's Blades Norman Osborn Obscura Alleylurkers Paleontologist's Pick-Axe Pharaoh Rama-Tut Pip-Boy 3000 Pirate Hat Playable Delusionary Hydra Pollywog Symbiote Pollywog Symbiote Prowler, Clawed Thief Rewrite History Rona, Herald of Invasion Scurrilous Sentry Shipwreck Sifters Shoreline Looter Sidar Jabari of Zhalfir Silvergill Peddler Spellbound Dragon Sphinx's Tutelage Suspicious Stowaway Swordsman, Sharp Scoundrel Talion's Messenger Teferi's Tutelage Temmet, Naktamun's Will Teo, Spirited Glider The Destined Thief

All I know is that some of the cards from Theros that I thought we missed are still creeping up, so while an optimal buy-in isnt in the cards at this point, I still want to go over the set
Sac outlets are useful and protecting your key goblins is lovely as well in the right matchups