My grandparents have removed the dew claws off of all of their huskies as pups because, according to them, as working dogs, the risk of injury while pulling sleds and whatnot is fairly high. There have been no ill effects that I am aware of.
I agree with seaslug about tail docking. There's really no good reason for it that's beneficial to the dog. If the tail is injured later and has to be amputated then so be it, but tails are important for balance and communication. And I'd imagine that because the tail is an extension of the spine, docking causes spinal issues down the road.
It's like declawing a cat, which would be the equivalent of having your fingers cut off at the first knuckle. A declawed cat is more likely to have behavioral issues because 1) it can't properly defend itself by scratching or climbing to safety, and 2) it causes discomfort and excruciating pain. It's sad and infuriating when I see pictures of front declawed cats standing/walking on their hind legs and it's treated as cute; it isn't cute, they are IN PAIN! They're avoiding standing on their front paws because they HURT! I can see how it would be the same sort of deal for a dog with a docked tail, who might be in pain, and can't fully communicate.
Ear cropping can prevent ear infection in floppy eared dogs... But so does keeping the outer and middle ear clean of fur and debris. If ear infections are a regular thing and your vet recommends cropping, sure. Otherwise, is there really a good reason for it?