Let's be very clear, this would be an _alpha_ release, not a beta release. So extra features can still land. The main aim for a release is not to have a stable version, but to have an unstable version plugin writers and packagers can use to create installer and update their plugins. Also, more testers might be attracted this way to help fix the releases
The entire 4.0.x releases would be _unstable_. When it is stable, we would release 4.1.0.
So, it would be nice if the bugs you mention are fixed, but for an alpha release not the essense. You can compare it with Gnome, KDE, ubuntu which prerelease on a schedule independent of the quality of the work.