Erlikosaurus! One of the lesser-known but more standard-form therizinosaurs. :D I happen to really love therizinosaurs, such badass creatures with so little love. Giant-ground-sloth-ostrichy-bear-pig-elk-birds. XD

Therizinosaurs were fairly far along in avian evolution, and being denizens of the Cretaceous they had adapted their feather coats for more varied, seasonal environments. I've depicted the legs bare as in an ostrich, but the rest is fairly shaggy. As theropods closely related to a lot of dinosaur families with wing and tail fans, these features seem likely but probably less prominent. For display, baby-care, and defensive reasons only. A thick thatch of quill-filled feathers on those long arms seems like a good way to deflect a dromaeosaur's or a megaraptoran predator's jaws, especially in such close proximity to those scary-ass claws. Would not be a great idea for predators to miss their target the first time around these guys.