Have you measured his back?
Ask him to stand square, and then move to his shoulder. Have a piece of chalk handy. Feel the top of his shoulder up towards the wither, then move behind the scapular where the gullet would sit. Mark this spot. Then ask a friend to lift the ponies' leg, mark where the...
I would up the haylage first. Try this for 2 weeks and then look to see if you are finding the improvements you're after.
For 'cool energy', you could look at adding oil. Barley is quite low in the fizzy-scale if you're into feeding grains. Ideally you're wanting lots of fiber to keep things...
Without seeing the horse and palpating, it's incredibly difficult to give advice.
My first questions would be what are:
Age of the horse
Any previous injuries
Was the horse raced
Any injuries in the float, flipping over, falling, slipping, etc
What are the heel heights/balances like on the...