... But Uriel was not speaking to counter Mab. He's not allowed to! His seven words are a direct counter to Lasciel's lie that made Harry lose hope and commit suicide. If Lasciel hadn't spoken to Harry in Changes, and he still came up with the Kincaid plan, Uriel wouldn't have been allowed to speak his seven words. Because he's Uriel, the words he chose also had the best possible effect toward bolstering Harry's resolve against Mab's control. And the Harry they get from it is better for both Mab's and Uriel's purposes.
I'm gonna go back to Ghost Story (which I don't have to hand, at the moment; so I'll need to paraphrase)...
After all the central "action" is over, and Harry's going through his "debriefing" with Uriel (but before he wakes up in Mab's lap), Harry says to the Archangel something snarky about how Uriel "always just deals with issues one at a time, lined up and separate, never taking two birds with one stone" (meaning, of course, the exact opposite -- that Harry absolutely does
NOT think Uriel works that way... likely often takes
many birds with one stone (not merely
two, as an aspirational mortal might)).