As you have access to the Ink ramp of Sapphire, try upping the count of those cards
It's worth bearing in mind that none of these decks are likely to hold up against a custom-constructed deck - there are way more powerful deck lists floating around the Disney Lorcana meta right now
By mastering the Sphere Grid, each of your creatures will level up with helpful new keyword abilities
Borderless woodblock cards can be found in non-foil and traditional foil in Play Boosters and Collector Boosters
Outside of removal, there's other powerful spells like the game-ender Exsanguinate, and the value engine Lingering Souls, both of which work well with Y'shtola's abilities due to being greater than mana value 3 when cast
Its only issue, really, is a lacking of an overarching strategy that makes this deck feel more like a greatest hits album and less like a cohesive strategy