You're probably right about the color, are you using smooth preview? Again, it's the legacy viewport in the final stages of life. If you're only using it for the shading, why not use a custom blinn or lambert in VP2.0 with a darker diffuse, or turn off color management and use the default?
This renderer is very strange :/ i wont use it anymore. In smooth preview it shows the poligons nice but when i change to normal mode it turns the mesh green like it has a million poligons i dont know but it seems that it wasn't a problem with the mesh or shaders. Anyways like you said i can use a blinn with a darker…