Don't blame you one bit, up close and personal professional eyeballs watching, testing by examination and evaluating test outcomes, is the best way but very few in my experience would know beyond offering standard swing fare where to start like you suggest. A good way forward starts with considering angular momentum will chase, and seek to align with, torque making the hands a more subordinate but predictable participant. The body hits, the club strikes, the hands hold. In some sense knowing your flexibility and mobility are basically predictable could be an asset, and I'm guessing it would, during the test. Good luck.