To make things easier, start by sorting your collection by rarity to find the expensive uncommon, rare, and mythic rare cards
That means cutting cards that dont cleanly fit into either role, or which are redundant versions of effects we have already graveyard decks can easily access huge chunks of their library each game, so variety is more valuable than depth
Two-color decks that dont have access to much ramp and can afford a few colorless mana sources can make good use of a Myriad Landscape, whereas green decks and 5-color commanders have much less need for something like this
He could even make a decent Commander, albeit one that limits you to a mono-white deck
We also needed something for chocobos to do, and the saddle mechanic didn't exist yet due to the development timelines of Outlaws of Thunder Junction and Aetherdrift