Here are some strategies to optimize your collection with grading in mind: Prioritize Condition: When acquiring new cards, especially rare ones, prioritize their condition
Its worth understanding that you cant use Japanese Pokmon cards competitively outside of Japan

Beyond those suggestions, it really depends on what you think the deck is lacking the most: Red Wraths: Blasphemous Act, Rolling Earthquake Flash: Vedalken Orrery, Winding Canyons Sac Outlets: Ashnod's Altar, Phyrexian Altar, High Market Removal: Swords to Plowshares, Path to Exile, Grasp of Fate, Council's Judgment Card Draw: Wheel of Fortune, Mind's Eye, Chandra, Flamecaller, Skullclamp Ramp: Solemn Simulacrum, Sol Ring, Chromatic Lantern, Coalition Relic, Chrome Mox, Mox Opal, Mox Diamond, Mana Crypt, Mana Vault Protection: Boros Charm, Avacyn, Archangel of Hope, Glory, Flagstones of Trokair Tutors: Enlightened Tutor, Weathered Wayfarer, Tithe, Idyllic Tutor, Land Tax, Stoneforge Mystic, Godo, Bandit Warlord, Expedition Map Stax: Winter Orb, Static Orb, Cataclysm, Armageddon, Ravages of War Anti-Control: Stranglehold, Grand Abolisher, Price of Glory, Homeward Path Lands: Clifftop Retreat, Rugged Prairie, Plateau, Sacred Foundry, Arid Mesa, Strip Mine, Wasteland, Mistveil Plains (lets you re-use cards with Sunforger) I don't often do this, but here's my take on a blinged out Archangel Avacyn, where money isn't an obstacle: We've got the White Value Package for card advantage / ramp / library manipulation, a Sunforger Package that can be re-used with Mistveil Plains, Mass Land Destruction once we're ahead on the board, and numerous combo combinations involving Adarkar Valkyrie, Kiki-Jiki, Mirror Breaker, and Ashnod's Altar

For text-only proxies, yes
Pull rate from Rare Packs: 3.85% The estimated pull rate for Dialga ex (Space-Time Smackdown) from a Rare Pack is approximately 3.85%, meaning you might need to open around 27 Rare Packs to obtain it
For the same reason, outside Engines are not recommended, even if they contain Spells (e.g