Materials color variation among elements

Hello D5 team ,
I would like to request a feature that enables color variation with control for example:
when we add wood material to wood planks I want to vary the wood darkens and brightness a bit to look more natural even in tiling and so it adds so much realism and depth.

TIP: in vray we do it but connecting multiple material node that contains shades of gray and mix it with the original diffuse map and making its blending mode soft light for example so it will variate the hues a bit to make it more natural while setting it random by element .