Your modeling efficiency on your guns is a bit better than that insect. 4k tris for the bug seems way over what it could be, could we see the wireframe?
Here's an Ambient Occlusion pass, and a wireframe of it currently, I'm currently working on attaching the back bridge to the front bridge, as well as working on some more detail in the merchant stand
It's all about edge flow. Lets see some wireframe shots. http://www.polycount.com/forum/showthread.php?t=80005 http://www.subdivisionmodeling.com/forums/showthread.php?t=8911