Contract from Below is actually better for the most part than Ancestral Recall, the discard aspect is often more of an advantage
As Cosmic Crucible's last ability is resolving, you choose whether or not you want to create the copy
Brawl Not Legal Vintage Not Legal Timeless Not Legal Commander Not Legal Pauper Not Legal Oathbreaker Not Legal Penny Not Legal Toolbox Notes and Rules Information for Claire D'Loon, Joy Sculptor: After Claire DLoons enters-the-battlefield ability resolves, any token you own that leaves the battlefield will remain in existence in whatever zone it goes to
(Crash course, courtesy of Wizards of the Coast: Nicol Bolas is the youngest and most powerful of the Elder Dragons to have survived the Elder Dragon War, filled with rage, envy, and a boundless capacity for violence
It opens up the possibilities for casting ridiculous X-mana spells
Tribal themes are hard to include in any sort of draft format without making it narrow, dull or imbalanced and cube is no exception