Ral, Monsoon Mage / Ral, Leyline Prodigy Ral, Monsoon Mage is fantastic on its own as a quick way to cut your spell costs and is a Birgi, God of Storytelling away from storming off
Almost every set has alternate frames with unique styles and art for the marquee cards, and the bonus sheets also get multiple art variations
In theory, there could be decks that don't want Glasspool Mimic (ones that have almost no creatures), but even with just a handful of creatures worth copying in your deck, it's significantly better than the Island it will likely replace
Shock lands, triomes, Eldraine lands
While 1,000 power might not seem like a lot, Zoros strategy can consist of spamming the board with low-cost characters that, with Zoros ability, can become huge threats if not dealt with quickly