One thing that could be noticed is that chronologically, anything before Edison would not have lasting staying power, and anything after HAT would venture into the premodern era post DUEA
Whispers of the Muse (T1, Ext, S, Block) A favorite in "Turbo Xerox" (a blue deck which used minimal land but a ton of cantrips to thin out the deck), Counter-Phoenix (Shard Phoenix + Forbid) and Tradewind-Awakening (put Awakening on the stack, tap all your lands for mana, untap all your lands), Whispers has what might seem like a hefty price to pay for one card but you get to do it turn after turn after turn
Astrologians Planisphere might actually fit well in a more tempo or artifact-heavy UW build, possibly with Cryptic Coat in the mix
The threat of a huge burst of damage on the way out makes this a shocking rattlesnake, and one you should deal with before it even starts to charge up