One of the problems that GitHub and GitLab are going to face in the coming years, as Git gets supplanted whatever wins, is that "Git" is in the company name. Those names are going to sound they like provide yesterday's tech, in a hurry.
I don't see a venture-driven way to be the thing that replaces Git. And I don't see a way to replace Git without being developing in the open. So, no GraceHub.