While it's not being published by FAKKU, Denpa is publishing an artbook by Range Murata that contains (among other things) stuff that he did for Kairakuten. I don't know if it includes any stuff from after FAKKU started its subscription service or not (the book is titled Futurelog, whereas the stuff on FAKKU has been titled Futuregraph, and I don't know what the difference is), but either way, the book is available on places like rightstuf if you want to get it. If it does include stuff from after FAKKU started its subscription service, then I think that it's safe to say that FAKKU isn't going to end up publishing it outside of the subscription service regardless of whether they'd consider releasing artbooks of anything in their subscription service, but a Range Murata artbook is getting published in physical form in the US.