Most of the time, criticism of git can be summarized as "Bad user experience", which is often blamed on git exposing its implementation details. I.e. most git criticism proposes that the backend of the VCS should be "private" and the user should see a carefully designed UI, that is optimized for workflows.
I think we don't need to redesign git in such a way, for the mere fact, that we already have a mature, distributed version control system that has a carefully designed UI and has a core that is opaque to the user: mercurial
In fact, given mercurial's age, the availability of github-like hosting services (bitbucket offered mercurial hosting for years) raise a very important question, that I would like "git-reformists" to answer as part of their critique: Why has git won more market share than mercurial?
My feeling is, that part of what makes git hard to new users is a "killer feature" for intermediate and advanced users. I.e. having a basic understanding of how git manages its data makes hardly leaves me with situations and repository states that I cannot resolve. Whereas in mercurial, I feel pretty much lost when I want to do something that has not been an implemented workflow.
Maybe, now that we know a lot more about DVCS workflows than we did at the time when mercurial and git were young, a new workflow-oriented VCS might make better workflow choices. Until then, I happily stay with git.