Is there an invisible monster in the centre of the frame that the aircraft is afraid of?

For once I'll speak up in saying that I see little point in moving the aircraft to the edge of the frame when theres nothing there to fill the empty space. Other aircraft, interesting scenery, smoke trails etc can all fill the void, but not a consistent background.

At least in my opinion.

When you do a motion blur, select a portion of the rear edge copy, paste onto a new layer, then apply motion blur again, only this time , make it more radical, it will look like the plane is actualy moving.

Then brush in some streaks from the highlights, like window corners of leading edge points.