Blue Elemental Blast's counter/destroy modes only affect red, which this Azorius Standstill deck doesn't play, so leave it in the sideboard — withdrawing that swap. Annul is the better addition, countering Powder Keg, Phyrexian Furnace, Humility or Standstill outright, and is a cheap way to stop their artifact-based board wipe piece. Decree of Justice is a sorcery, so Annul can't touch it; handle that with Counterspell and Foil instead. Daze is weak since they can easily pay {1} with their lands, and with Mana Leak and Counterspell in their deck the tempo loss from bouncing an Island is risky. Flash of Insight is too slow against their Standstill-centric control plan. Protect the Dreadnought and race before Wrath of God punishes overextension, and be careful about casting spells into an active Standstill; keep the core engine fully intact.