Good thots, OG.
To be honest, I don't know when the Viper FCS ignored AoA or didn't. Best I have in documents is that it was used as long as we had WoW switch decompressed. When I did a tail slide one day all the warning lights came on ( AoA sensors at limits, calibrated speed below 120 knots) and without resetting them, I had complete control once the nose fell thru. Reset the FCS panel and fight was still on, heh heh.
OTOH, the A-7D and other jets displayed the AoA whether the plane had a FBW system or not. Viper didn't, as some folks the braket was a nuisance symbol in the HUD.
I learned in planes that had very clear warnings you were approaching a stall. In later planes, we had buffet and wing-rocking and such to let us know we were reaching the edge of the envelope. It was a different feel than when nearing critical mach, which usually exhibited stuff like aileron reversal, nose tuck and a pronounced "buzz" in the airframe as the shock waves formed.
So my thot is that a display should be available and right in front of the pilot whether the FCS or Otto is using it.