Elaphrosaurus was a fairly basal theropod dinosaur. The Late Jurassic, however, was a time of radiative adaptation by theropods in the eat-or-die arms race of evolution. How a rather basal theropod was successful long enough to appear in the fossil record could be a point of contention, but it is possible that even smaller populations of species can appear in the fossil record as well. That said, this illustration of Elaphrosaurus does not create a very likely picture of a highly successful carnivore. Instead this illustration of Elaphrosaurus makes the theropod look more appropriate as an omnivore or at most a carnivore whose diet would consist of small mammals and lizards. Perhaps, given the small size of Elaphrosaurus compared to apex predators such as Allosaurus, this diet and this look would be ideal for a carnivore like Elaphrosaurus.
Appearing more like Dilophosaurus in this image, this Elaphrosaurus interpretation appears much more vicious in terms of carnivorous appearances. Regardless of how much more of a larger game hunter this Elaphrosaurus would have been, it would still have been the same size as an adult as would have been the previous illustration. The skeleton on display in Berlin, however, does not have any crest on its skull. The crests pictured here are speculative and are not present on known specimens of Elaphrosaurus. It is possible that Elaphrosaurus had some sort of dermal crests, but these sorts of soft tissue protrusions have not been preserved in any known specimens to this point that has been described.