Angle of Attack varies as a vector with speed,
Not sure I understand what you mean by that. An angle is an angle, isn't it?
and also with the upwash induced by the wing. Upwash is in turn variable with the wing configuration, airflow velocity over the wing, and angle of attack. Increase angle of attack, increase downwash behind the wing and upwash ahead of the wing, and angle of attack increases beyond the simple angle made by the free airstream and the wing chord line...local angle of attack is greater because of upwash.
OK, so the changes you're talking about are in what you term "local" angle of attack, which includes the induced flow from the effects of the finite wing. So for the same downwash velocity, the induced AoA at the outer tip is less than at the inner tip because the forward velocity is greater? I can buy that, though I don't think that's a conventional use of "angle of attack", which is the angle to the freestream (before the aerofoil has had a chance to perturb it).
During a climbing turn, the outer wing tends to have a higher AoA, and during a descending turn it's the opposite.
Wouldn't you regard that as the climbing turn being "less stable"? A higher AoA at the outer wing tends to roll the aircraft into the turn. Conversely in a descending turn the higher AoA at the inner wing tends to roll it out of the turn. The turn may still be unstable because the total lift from the outer wing may still be higher, but it's more stable than the climbing case.