Reguarding sunglare (Disclaimer: I've never been in actual combat but have gone outside on rare occasions)...
The point is not that the plane vanish when within the disk of the sun, they do. It is more an issue of attempting to simulate that it is unpleasent to look anywher in the vicinity of the sun. If Blocke had of needed to line himself up perfectly between the Sun and his target in order to avoid being seen, as we would need to in AH, he would never have even mentioned it. The Sun is what, only 1/2 a degree wide or so, that leaves little margin for error if one wants to play the part of the "Hun in the Sun."
I think Chefer's point is that there exists a disk, a good deal larger that the disk of the Sun itself, in which the glare of the Sun hide the attacker. Further, there is a larger disk around that in which you don't want to look to often because it is unpleasent.
My suggestions:
1) That planes progressivly loose contrast the closer they get to disk of Sun until they vanish. I believe they currently do this but I'd like to see the "effective" disk be about double in size.
2) That planes within an arc of about 4 disk diameters have no icons.
3) That any time you look in the direction of the Sun, for a period of time dependent on how long the Sun was in your field of view, you see the world as if it were night in other directions.
