Another underrated model. It is a fair TT standard, so I rate it 5.
As with your other models, its face and base that lets you down. With this model, I would add the metallic parts to that.
If you want to improve it, either wash entire metallic area with GW Devlan Mud wash and when this dries, add some GW Badab Black into the deepest recesses, and after that dries drybrush some GW Boltgun metal over the raised areas. I would rather repaint the armour entirely though, as it doesn't look good in metallic. Black, brown or dark green are much better colours I think.