This is by far one of my favorite Skaven models. I am planning on doing another one just to see how much better I can do with it. Constructive critism welcome.
You really need some shading, as well as some highlighting. Also, your paint seems a bit thick (especially the red parts), are you sure you thin it down enough?
Also, try not to stick too much things on one money, it will suffer from overkill.
More highlights and shadows would help bring it out. The metals, especially, seem a bit flat. Easy things to do would be to run a dark wash over the folds in the tubing and other highly textured areas, or a bit of shadow around the rivets followed by a dab of bright silver on the rivet head. Many painters do colour transitions along horns, too. From a colour perspective, you have a bit of a rainbow, with nothing dominating. Your rat ogre unit is more eye-catching, with a strong green/yellow look with just a few red accents. The definition on the top rat-face icon is really nice, and the hanging bone is great.