It might help to think of driving your hips through more.
Also, since there is a problem with your air position, spending some time perfecting your backspin position and going back to waltz jump/back spin drills or even a single axel focusing on body position in the air could help. You probably have a similar problem with the lower rotation jumps, it's just not as pronounced. Fixing it on the single could help the double.
Yes, is true I have also the serious problem on air position, the legs are also not straight, and the rotation is not fast. Good idea for axel with back spin, I will try it.