Three things really stand out to me in this deck.
One, unlike Blue Moon decks in the past, this one does not play Spreading Seas for additional mana denial, instead opting to play more reactive cards. Since the deck is mostly blue, you can play a ton of basics and still make Blood Moon good, but you don’t need the entire gameplan to revolve around it. As a result, you’re not nearly as dependent on Blood Moon, which is the best of both worlds.
Two, Torrential Gearhulk in Modern sounds sweet. These decks always lacked a great win condition, so having one that dodges a lot of commonly played removal, trumps most other creatures on the battlefield, and functions as an additional copy of any of your answers is the ideal. Reactive control decks have typically had issues in Modern, since they needed to play some expensive sorcery to close out the game, and finding the correct spot to play it and turn the corner is at best a difficult decision to make correctly and at worst impossible. Having a flash threat lets you continue to react to your opponent and always land your win condition on the right turn, a subtle but important upgrade.
Plus, flashing back Cryptic Command with is so sweet. Possibly too sweet. In fact, I’m going to give you all a second to think about it, bask in its awesomeness, and recover before continuing.
Everybody set? Good.
Third, I was taken aback by the full four copies of Ceremonious Rejection in the sideboard. It’s a seemingly narrow card but it actually comes in in a lot of matchups. It’s great against Affinity, Bant Eldrazi, and any form of Tron, so with Eldrazi Tron rising in popularity right now, Ceremonious Rejection is quite well-positioned. Taking advantage of cheap spells that would be too narrow for most metagames but are appropriate at the moment is among the most important parts of tuning reactive decks like this, and having the confidence to make the jump from one or two copies (where you won’t get burned too hard if it underperforms) to four is a nice bit of deckbuilding.
Modern is slowing down right now, which is great for control decks that want to prey on midrange strategies, so Island devotees unite and get back to some good old-fashioned draw-go Magic.