In some ways, it's not actually an amazing card, since this is a six mana spell that does nothing if you don't have a good board state
Remember that the cards at the bottom of your mana curve should be cards you actually want to cast early in the game
Five mana is slightly high, but in Treasure-based decks, you can generate five mana with ease
This is doubly true of typal payoffs that care about how many of the supported type of creature you control, or ones with creaturefall effects that want to see more bodies enter the battlefield
Saheeli, Sublime Artificer I think Im less excited about Saheeli, Sublime Artificer than some of my peers, but I do recognize the value a Young Pyromancer proxy that isnt targetable by creature removal can potentially provide
Timing this move well can swing the game by removing key threats without needing to hit massive numbers