Is it ridiculous? Could definitely say so, but I legitimately love the coincidence. I find it bizarrely cathartic, how Kiki was her inspiration all along and how it came full circle with the two uplifting each other and all.
As for the confession, honestly, the pure shock from Kiki was perfectly conveyed, in my opinion. Especially how the fact that this is something that happens to her at that moment just hasn't sunk in yet. I also understand why Michiru ran away, considering the response, and hope and expect them to go through this. Hopefully soon, ideally to me, Kiki immediately realized "wait that actually just fucking happened" and runs after her.