You can't really see it in the render, but I am hoping the Trebuchet's left elbow is more like a human joint than the right one is.
It seems like MWO has introduced a new era of elbow design into BT art, where the rest position is bent 90 degrees to point forward, and it often doesn't look like the arm can be fully straightened. I think that makes a lot of sense for a gun arm, like the Treb's right arm, but it seems like a strange choice for a humanoid arm with a hand at the end. The great majority of classic (old?) art used more naturalistic joint designs.
This comment is not truly specific to the trebuchet, but it happened to catch my eye in the recent render.