Draft crosses, particularly light drafts such as Friesians, Irish Draughts and Cleveland Bays (which, whilst being light and used for riding/carriage driving/hunting, they were originally also bred for all-purpose farm work, so still count as light drafts!) can make very good dressage/eventing/showjumping horses. The call these kind of crosses 'sport horses' over here - Irish/Friesian/Cleveland Bay Sport Horses. They are very nice, athletic horses with a bit more to them than a TB. However, a decent sized warmblood should also be able to carry you at 185lb. They are better weight carriers than pure TBs, and a decent 16.2-17hh one would carry you fine. Or even middleweight hunter type.