I have an idea that may address this problem. The military are of course familiar with these.
What about installing drag shoots for braking. As some of the speeds mentioned the chute maybe the only way to retrieve the situation to a manageable level.
Why not have a net installed at each end of runway. If the controller thinks there maybe an over run he could have the net raised. Or it could be automated. Not sure what sought of installation would be needed to stop a runaway A380. Quite substantial I would imagine.
