Why, for the love of all things Magic, do you not have Chance Encounter in this?
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This deck is built around mono-red. Splashing white just for the Archangel would throw the whole deck out of balance and ultimately leave it awkward and clunky.
Which is why both options are present in this deck; you can choose your method of murder based on who you're playing. If you're playing against blue, expect a Redirect and go for infinite Propagators. Playing against green, slap them upside the head with Fireball.
The point is that Hive Mind forces your opponent to cast a copy of Intervention Pact that turn. If they have no white mana, guess what happens on their upkeep?