I have been lucky to get full access to Show center of an Air Show (best position in regards to sun and the show itself), and want to get the most out of this unique opportunity photo wise, so I'm looking for tips and advice here.

My gear is:
air shots:
Canon 5DM3
Canon 70-200mm II f/2.8
Canon 100-400mm f/4.5
Polarization filter
Monopod/tripod

ground shots:
Canon 24-70mm f/2.8
Canon 50mm f/1.2

I'm aware of the risk of underexposing planes on a bright sky which is my main concern, but not sure what would be "best practice" or procedure to avoid this. I'm aware of the need for fast shutter speeds (fx. min. 1/400 on a 400mm lens) of around 1/800-1/1000 for jets close by, and slower shutter speeds for propeller planes etc. I'm a happy amateur but pretty comfortable with my gear and settings, as well as post-production in Photoshop.

But my main concerns are:
1) What is "best practice" to avoid underexposed planes on a bright sky? If you compensate exposure, I'm afraid to forget to check this if the light changes during the day? What is your experience? Is there a "rule of thumb"? Pol-filter or not?
2) Av or Tv mode? The Image Quality on the 5DM3 with higher ISO's is amazing, so light shouldn't be a problem. But what is preferable?
3) AI-servo or not? Seems obvious, but then if I choose fx. a center focus point I'm afraid I won't have enough sky in front of the planes for best composition? If I use a focus point on either side, I would have to change this all the time as the planes are all over the place? What is your advice on this?
4) On the 5DM3 there's 6 AF-modes for different action situations. Any advice if one is much better than another?

Anything else?

Do you know of any pro Air Show photographers with a web site with inputs on this. I found articles, but usually the just sum up the pro/cons and don't end up with more specific answers.
I appreciate all your inputs and advice and hope to be able to post links to some great pics here later.

Thx.