I much preferred the amber light on the side mirrors of my previous Audi. For a start, the side camera image should be near the top of the screen, even if it temporarily covers speed info etc.
Fairly sure that'd be illegal (covering the speedometer)
Upper right would be possible I suppose.
I too would prefer a unique audible alert if a car is in my blind spot.
There is one if your turn signal is on and you actually attempt to change lanes at all (and have this alert activated- I posted directions to do so earlier in the thread)
Playing an audible alert EVERY time a car was in your blind spot, even if you're going straight, would be incredibly annoying.