Thanks @andreaspeijerb, I'm so glad to hear this was helpful to at least one person! (I also plan to refer my future students to it, so it's useful to me I guess even if no one else reads it.) And congrats on making a hard decision with what sounds like a lot of honest soul-searching. (3) sounds like an especially decisive factor.
And I'm sorry to hear you ran into academic politics. I've heard similar anecdotes about the "soft sciences".