While you might feel a bit limited with just mono-blue, this commander can churn through your deck or copy important spells once you resolve a couple of prowess triggers
Gaea's Cradle The best MTG land you can actually play An land only needs to produce two mana when you tap it to be, objectively, broken
The hype seems likely to continue carrying this card into the stratosphere.
Even though some of the rooms or whatever may be a bit boring/bad, most of them are really strong, and as mentioned before, they cover a wide range of desirable effects in the game
It may be slow at 6 mana, but Archetype of Imagination can effectively make your fliers unblockable (reach aside) by hating on all your opponents' flying creatures
The only time this is a really good thing to flop out is against red and/or black decks and even there she isn't the auto win that Sphinx of the Steel Wind is against red and/or green