I have now had a chance to try out different media in the Hahnemuhle Black Book.
At the top, I have printed two of my foam stamps, plus two Softcut images - all using white gesso. Once dry, the first three images were coloured with acrylic inks, the fourth with metallic and coloured pencils. All these were successful.
Bottom left, is coloured pencil - I think the "tooth" of the paper worked well here. I expect pastel will be good too.
Bottom right - gouache. At 120 lbs the paper is quite sturdy and there was no problem using wet media.
A nice paper to work with.