[EdZ]

The right elbow should move back and through on 'its' plane. Extensor action should be your goal, 'letting' the elbow bend is good, but trying to 'tuck' the elbow in, or holding against your side isn't (unless you are able to maintain your radius and center with a steep shoulder turn).

An image Yoda taught me re: the elbow position/right forearm was to imagine I was going to 'spear a fish' at the ball, or alternately, think of a right handed javelin throw through the ball (to your aiming point). The motion is basically the same, except you want to keep that right wrist bend. Keep that javelin 'in line' with your forearm, and your elbow will take care of itself.