I have made several blends of tones on Canson Platine Fibre which works best for me for these new inks. However I can hardly reach a neutral tone and not any blue staining. It would be great of the cool inks could be a little more blueish.
Canson Platine is a very warm paper as it has no optical brighteners. A more blue paper would be something like Epson Exhibition Fibre or (even more) ILFORD MonoSilk.
There is a significant diminishing in returns related to archival qualities and more color in the blue as base carbon is nearly the exact opposite of blue.