I understand the mare photo is poor - my apologies. If you can take a look at the Stallion, it would be appreciated. I plan to use the offspring for amateur dressage, as to achieve what level, I am not sure. I am a recreational rider - I do not compete at high levels. I currently work with a level II Dressage coach (Canada).
There is not much not to like about this stallion for a dressage prospect offspring, and the potential for medium and above when paired with the right mare should be very favorable.
He has great substance (based on that alone I would not have guessed him to be a Trak), the low knee and long forearm needed for the right kind of movement and ability for lateral movement.
The angle of the photo is a little off so determining exact shoulder slope and angle is difficult, but they appear to be more than adequate with the shoulder laidback and the angle open.
Excellent length to the humerus bone. The pasterns are medium in length, as is the back.
The hip is long, the loin coupling strong and deep. The hock and stifle are also well-placed.
My biggest knock on him, for you, is his size. 17.2h is a lot of horse for a recreational rider to ride. The amount of power and movement compared to an Arabian is, frankly, not comparable. Controlling the haunches, keeping the horse straight, and all that goes with it, is a daunting task.
It's quite possible you won't get such a large horse with an Arabian mare...but here comes my next concern...I never like to breed a bigger stallion onto a smaller mare. Nature is clever, and usually finds a way to adapt, but not always. The risks are increased for such a pairing.
I believe you'd be better served breeding your mare to another Arabian...or, if you're desire is to improve your chances for getting a dressage suitable offspring, then breed her to a Lippizanner stallion...particularly of the Siglavy line, though any line has a high chance of success.