VRayMultiSubTex (or similar) question

I have a stupid problem with a half solution...
I need to have lot of objects with SAME material, but DIFFERENT colors.

MultiSubObj is my current choice, but material tree is very big and complicated and I need to switch to something more clever.

VRayMultiSubTex is the best solution.... but the problem is that it does not let me view its different colors in viewport, and working in this way is a bit hard.

Does anyone know a trick or maybe another map or script or something to solve this problem?

Thanks,
Ste