Linda is different from the other savages because she's not from the reservation, she's from the Brave New World, and she still lives by the standards of that society. She is promiscuous, and still shares many of the same values of those conditioned clones in Brave New World. John is different because he is the child of an affair between Mustapha Mond and Linda and is an outcast from birth. John is tall, noble in heart, and very handsome. These qualities might not be as prevalent in the reservation's men--with the exception of nobility, of course.
Lenina is disgusted by Linda because during her time on the reservation she has become old, wrinkled, and fat. Linda is not as beautiful as she once was.
Having read Shakespeare extensively, John develops a complexity of thought that alienates him from the others on the reservation as well as later in the New World. Blond-haired and with blue eyes, John does not match any of the other savages in appearance, and he certainly does not match any others in intellectual considerations. In fact, he seems an incarnation of a Shakespearean hero: complex in thought--too complex for either world--and tragic in nature as he cannot reconcile his lines from The Tempest ["O brave new world"...]with what he encounters in the New World.
At the novel's end, in fact, allusions are made to Macbeth-- "And all our yesterdays have lighted fools the way to dusty death"-- and to Hamlet-- "And yet that same Gloucester had called them ever-gentle gods.....No more than sleep. Sleep. Perchance to dream....For in that sleep of death, what dreams?"
Like Macbeth, John the Savage finds himself in the "shadow" of death, and looks up at the helicopter of his destruction that looms overhead; his mind wanders "in that other world of truer-than-truth." John cannot fit into either the reservation or the New World of conditioning and falseness of life; thus he enters "that sleep of death."