Definitely think adding red chipped paint helps alot, brings the connection like others are implying.
I noticed something myself too, when i looked at the images (last ones form Canny) the one from the back looks more striking to me. And i noticed that in that particular photo you can't see the Tyranid claw (might be the angle of the photo too though...).
so I did some quick Photoshopping on the 'front-image' and shopped the claw out of the image. Also added some dark greens and dark spots to the base.
I'm not implying to take the claw away, but for me it is not really on the same level as the rest and although not a huge one it is distracting me a bit.
Maybe something to think about or something for others to give some feedback on...