This seems fairly well optimized. There's probably room to squeeze out some more perf, but not dramatic improvements. Maybe preventing overdraw of shaded pixels by doing a depth prepass would help.

Without digging into the detailed breakdown, I would assume that the sheer amount of teeny tiny triangles is the main bottleneck in this benchmark scene. When triangles become smaller than about 4x4 pixels, GPU utilization for raterization starts to diminish. And with the scaled down dragons, there's a lot of then in the frame.