Some additional metadata would be useful:
- the user who pushed a commit
- the user and date associated with pushing a specific version of a file or directory
In principal, the date is retrievable by following the history back for a particular commit.
The username is not persisted, though and it might be better to keep it as per-blob metadata or carry forward with each commit. As an alternative, each blob in a commit could point back to the commit that originated it.