The smaller packages that I discussed with artifacts, pingers and deathtouch effects, retrace cards, flash enablers, and cards that cast other cards all work together in the deck to trigger Jori En and have a steady stream of cards flowing
Mint or PSA-graded cards will always fetch more
Here's all of the Rare League Cards you can pick up in the post game, plus where you can find them: Milo's Rare League Card : defeat the dynamax Tsareena at the Turffield Stadium Nessa's Rare League Card : defeat the dynamax Gyarados at the Hulbury Stadium Kabu's Rare League Card : defeat the dynamax Torkoal at Motostoke Stadium Bea's Rare League Card (Sword) OR Allister's Rare League Card (Shield): defeat the dynamaxed Pokemon at Stow-on-Side Stadium Bede's Rare League Card AND Opal's Rare League Card : defeat Bede in Ballonlea Stadium Gordie's Rare League Card (Sword) OR Melony's Rare League Card (Shield):beat the dynamax Pokemon at Circhester Stadium Piers' Rare League Card : a reward from Piers after capturing Zacian or Zamazenta Raihan's Rare League Card : defeat the dynamax Haxorus at Hammerlocke Stadium Rose's Rare League Card : a reward from Oleana in the post-game

Character(C)Toho Yu'Gi'Oh(C)Konami Illustrated by Art Adams Note: I listed him as a Earth type of card because of the other cards like Ultimate Tyranno, Super Conductor Tyranno, and many more dino types
Momentous Fall, these cards do functionally the same thing and have their pros and cons
Reaper of Flight Moonsilver requires delirium, which might muddy the plan