It cracks me up anytime someone posts that they are above 200 lbs.mostly everyone else on this site thinks that the only horse that can hold them is a heavy draft, clydesdale, etc. My husband is in that range and rides the most wonderful Missouri Fox Trotter with no problem. He also rides my Paint/Paso mix who is much smaller with no problems. It's all about what the horse can handle and his build. Now, don't get me wrong, my Paint/paso could not handle him for an endurance ride, but he has been fine on trails for a couple of hours with no soreness at all.
It really depends on what you are looking for in a horse. There are some great Quarter Horses out there that can do the job, as well as, Morgans, Fox Trotters, Kentucky Mountain horse, etc. You just need to look at the horse's build and conditioning.
Hope this helps!