Try listening to the AOA...
The short answer to the original question is that optimum indicated angle of attack is not affected by gross weight, bank angle, load factor, airspeed or density altitude...like an airspeed indicator, if the system is calibrated, stall will always occur at the same indication on the AOA display for a given configuration. If the display is in the pilot's visual cross-check, it can be quite useful when maneuvering the airplane as well as during approach and landing operations.
The VN diagram for my airplane depicts the optimum AOA band as ON SPEED (nominal 60% lift), and you can see how the band follows the aerodynamic (stall) limit and varies with indicated airspeed:
Long answer (from the "it depends" department!):
My RV-4 is equipped with an aural tone generator that utilizes the AOA serial data output of a DY-10A that comes from a standard Dynon differential pitot sensor. The tone processor begins a low frequency beeping at L/Dmax with the pulse rate increasing until reaching an ON SPEED (optimum AOA) condition (nominally 60% lift) and changes to a steady tone at that point. As the airplane continues to slow and AOA increases, the frequency changes to a high pitch and begins to beep again, with a high pulse rate stall warning provided 15% prior to stall. This tone allows me to hear the back side of the drag curve, and it will help illustrate how AOA works during maneuvering flight.
This video link shows what the back side of the drag curve sounds like using this tone logic:
https://youtu.be/S9H6T_tOLe4
Old F-4 pilots will immediately recognize the tone pattern, and fighter pilots will recognize that ON SPEED provides a basic reference for not only approach and landing, but also best sustained turn performance for speeds at and below corner velocity (maneuvering speed). The tone generator allows me to fly approach and landing and "max perform" the airplane without having to look inside the cockpit and helps me avoid pulling too hard and exceeding the aerodynamic limit (i.e., stall).
Since it's difficult to describe how this all works, it's easier to show you with some basic examples--here are some You Tube video links that might help illustrate the concept. Unfortunately, you can't see the EFIS in the video, but the back-up airspeed indicator is visible and provides a reference point. Also note that the tone has a volume control, but output to the camera is defaulted to maximum volume, so what I hear in the headset is not the same as what comes out on the video. The tone is not as annoying as it comes across in the video recording, but the loud volume on the stall warning is NOT adjustable (i.e., it's designed to be annoying!).
This video shows an ON SPEED base turn and final approach. The change to a high pitch tone indicates a "slightly slow" condition, the steady tone indicates ON SPEED and the change from steady to beeping is "slightly fast." The basic technique I use is adjusting pitch to control AOA (tone) and power to control glide path. It is a fairly wide pattern to provide maximum time ON SPEED for demonstration purposes. The final approach is a 3 degree glide path but may appear a bit drug in due to the distortion of the medium field of view mode on the Go Pro camera used to record:
https://youtu.be/IkuHyUuEB_w
To get to the original question in this thread, the next two videos show steep turns; and note the airspeed at which the ON SPEED tone occurs--quite a bit higher than what you saw when operating in the traffic pattern; but the AOA is the same, optimum, for both conditions. Roll into the second turn is more rapid, and you'll note a momentary AOA over-shoot on the initial pull. If you watch the video carefully, you can see the change of nose track with the change in tone--in other words, I'm reacting to the tone by adjusting G (how much I'm pulling) to keep the turn ON SPEED.
https://youtu.be/BphHzWHbOjo
https://youtu.be/4tvrWWtBEbQ
The next two videos show a 180 degree banked steep turn (i.e., a Split S), again note the relationship between the tone and indicated airspeed, the AOA is constant throughout the pull through:
https://youtu.be/kZJpk_hFIbg
https://youtu.be/nMXvd5MYC8k
The last video is a simple accelerated stall with an intentional secondary stall. The stall occurs when the nose stops tracking across the horizon. Due to the high G onset rate, you'll note that the aural AOA system is a bit pressed to keep up with rate of increase...in other words, if I pull hard enough, it's possible to "beat the warning" just like you can with a conventional stall warning:
https://youtu.be/DLtamTAh-Is
I hope this helps demonstrate some of the basics of what's going on with AOA during maneuvering flight. There's quite a bit of discussion about maneuvering in the training manual that is posted on the safety page that may also be helpful for folks interested in the topic.
Please note that I'm learning as I go with all of the video editing and sharing, so if there are any issues with the links, let me know and I will try to fix it.
Fly safe,
Vac