I think the answer to this question is that the Mapping Toolbox has never received due attention from TMW. I get the sense that its development has been primarily an underfunded side project. Perhaps the Mapping Toolbox would receive more attention from TMW if more people used it, but for people to use it, it would need to be developed further. Sort of a chicken or the egg scenario.
I recommend creating a north arrow manually, perhaps with annotation. You could also place a scale bar manually in projected coordnates. I wrote a function called scalebarps which automates scalebar placement and sizing. I wrote it for Antarctic projections, but you can use it for any projection as long as the axis units are meters.
