Dryptosaurus, as we can see here, was not exactly a complete skeleton. We have, however, seen fewer bones used to identify a species, and as such we cannot really say "Cope, what were you thinking?" Besides, Cope has had enough embarrassment, the poor fellow. The fact that, throughout the years, Dryptosaurus has stood up on such little leg evidence (puns? Oh yes!) as well as small amounts of fossil evidence from elsewhere in its body shows how little the remains have in common with other dinosaurs; that is to say that the few bones we have of Dryptosaurus retain their distinctive characteristics enough that we have not dropped the name as yet as a synonym of another species. Dryptosaurus has, however, been placed into a number of families over the years, starting out in the Megalosauridae and, through a rather laborious sloshing through Coelurosauria and Tyrannosauroidea (placement here was based on the closely related and more complete Appalachiasaurus- come back in two weeks for more on them) and finally in Dryptosauridae thanks to Kenneth Carpenter. Dryptosauridae is considered a subfamily of the Tyrannosauroidea these days.
Dryptosaurus, as a tyrannosaurid, is subject to the laws of feathering, as it has been applied to other tyrannosaurs. Nobu Tamura's Dryptosaurus has a nice mohawk of feathers and, very happy as it seems with itself, is brandishing the enormous claws which led to its specific epithet (aquilunguis meaning eagle clawed). Having stated my feeling on scaly dinosaurs a week or two ago, I like Charles Knight's scaly Dryptosarus; however, the feathered dinosaur version of Dryptosaurus looks equally valid and quite fantastic. The feathering on this version is not ostentatious and plays very well into the camouflage of the animal which must have been true, to a point, in order to aid in hunting; that is unless Dryptosaurus did not bother to hide at all and just simply ran down and clawed its prey. Feathering would, of course, keep Dryptosaurus a bit warmer than just being scaly, but was it necessary and did it really exist are two questions we cannot answer assuredly for Dryptosaurus at this time.
Feathering, and coloration, as I stated just a moment ago, have to be considered in coordination with the practicality of their use in every day life for an animal. A peacock does not camouflage itself well and sometimes pays the price, but most of the carnivores that live in our day and age, feathered, furred, or scaly, tend to blend in a bit better with their environment to aid in the success of the hunt. Great Whites mimic the surface from underneath and the deeps from above; tigers blend in to the grasses of India; bears in the woods mix with the shadows of the trees and bushes; hawks tend to have white ventral surfaces which at least vaguely look like clouds to the rodents below. Dryptosaurus, therefore, probably blended into its environment at least a little bit in order to hunt effectively. That said, I think the only thing in this version of Dryptosaurus which may be a little disagreeable would be a bright red face. The unfeathered body certainly blend in with the landscape of the Cretaceous grasses and even the shadows of trees, as would the dark feathers along the back. The white perhaps not so much and the red, unless dinosaurs were uniformly color blind (why bother having colors in that instance when patterns would probably be enough), would not help camouflage the dinosaur while it was stalking prey. That is my opinion, certainly feel free to develop your own!