Thanks for that, Chris. No fur, just a modified version of DR's bump map to define translucency and subsurface scattering. The textures are 4k, so that helps. For the Mental Ray Final Gathering/GI there's a diffuse bounce, which I usually have switched on as it adds a bit more realism. The right deinonychus's mouth might be picking up more light because the pink membranes between the mandibles are also translucent and light's passing through them, with added reflectivity inside the mouth. I take your point, though, and may add ambient occlusion to the mouth areas.
One thing that stands out to me is the absence of backlighting coming through the large feathers. That's because the feathers [on the head, arms and tail] are modelled and not textures on flat planes, and even though they're very translucent in the texture map they don't seem to want to play ball. I might look into that. Fantastic models for just over ten quid, though!
The golden rule of vegetation IMHO: leaves are reflective. Tried to get away with it in the first version. Fail.
