Actually, as long as you are comfortable, you look perfect. Flat back, arms slightly bent, good knee flexion/extension, not a lot of hip rocking, looks good! You could add a video from the front so we can verify knee tracking.
I would try elevating by a millimeter at a time, until pain due to hips rocking begins to be felt. Then back off a millimeter to stop it. This will minimize your maximum knee flexure. Usually a bit more comfortable for me.
I also find I need to reconsider and address new problems as my riding distance ramps up.