How wide

[air]

should the takeaway and backswing be?

And how near the body should the right elbow be? Should there be a gap or is it better to have the elbow so close into right side of the body as possible during the whole backswing?

[Mhairsto]

Try this:
Let the right elbow and right grip relax a bit, and sort of hang the right elbow down during backswing.

I've discovered that every time I remember to keep my right elbow lower, my right-arm-right-push early-turnover -over-right-gripped snap hooks and sometimes even my nasty slices are gone, and I usually get a very straight ball flight.

Keep that left arm as straight as you can - especially at the top of the backswing, BUT DEFINITELY at the start of the downswing, (DO NOT HITCH the elbows @ the top... JUST TURN @ the waist) and you will see immediate rewards. Let us know if this helps.

[Bobby_Eldridge]

If you turn the right shoulder in the backswing the right elbow will stay close to your right side in the backswing.