Archmages Charm is extremely pushed, a solid permission spell, a good way to build card advantage for hitting land drops, and a fantastic tool against Deaths Shadow, Wild Nacatl, Goblin Guide, Pyxis of Pandemonium, Champion of the Parish, Aether Vial, Delver of Secrets, Hardened Scales, Amulet of Vigor, Benthic Biomancer, Glistener Elf, Noble Hierarch, Viscera Seer, and sometimes even Hexdrinker (just to mention a few)
Zen Takahashi I will be the first to admit that I was in the camp that believed unbanning Jace, the Mind Sculptor would be a mistake
Blue-Eyes Spirit Dragon does little to slow down ABCs strategy, and ABC could easily fetch Ally of Justice Cycle Reader through Gear Gigant X to deny Blue-Eyes from Special Summoning from the graveyard
You can make specialized decks
If your opponents are still building their board states and dont have any major threats that need to be removed, it might be better to cycle for something you can use now, especially if you're in need of lands
That rarity unsurprisingly comes with immense value, too