Before full launch data, the strongest cards to watch are the Admiral Super Parallels, Ace Secret Rare, Blackbeard Secret Rare, Treasure Rare, and Leader Parallels for Ace, Luffy, Blackbeard, and Yamato.
This jump is a direct result of the Silverquill Influence deck and its commander, Killian, Decisive Mentor
Esper Sentinel Speaking of staples, heres Esper Sentinel
Crocodile ST03-003 was first released in the set Starter Deck The Seven Warlords of the Sea, illustrated by Eiichiro Oda
Its even got foretell to have a little extra functionality, whether you care about paying mana on the course of 2 turns or casting cards from exile
You may find that decks composed of cards from the same set may work better together, but the important thing is that if each player has two packs, they can just open, shuffle and play