My dog's breeder, von Goedehaus kennel, does all the desensitization with noises, uneven surfaces, different terrains/environments you describe and more. They are working line GSDs that are typically pretty high drive but they excel at jobs. A WLGSD might not be the right fit for you, but..

Kevin Goede, the breeder's husband, is a trainer and may know of breeders in their area of other breeds that raise their pups similarly and might be lower drive