If you would allow... Alter the camera angle so the horizon line is approximately one-quarter to one-third of the way up from the bottom of the working window: this will make your point of view far more dramatic. Because of the lack of shadows, Im assuming the raptors have been added in post work; if this is so, then go back to Poser and export them as .obj files, then import those into your Bryce composition. This will provide you with the means of making the lighting more dramatic and consistent. Finally, given the distant haze, Id suggest adding a ground-level fog to the piece: nothing more than settings of 10 and 70, but you will need to play with them depending on the scale of the Bryce piece. Give it some color, such as a medium gray, so that it maintains a presence without being overwhelming.