I have seen a few threads on here about how to level the waste board, and how there is no real good way to do this.
With the introduction of the Z Probe, it should be much easier to implement now than ever before. Within Easel, I would love to be able to have the system choose several points on my waste board to measure the distance between the spindle and the waste board itself. This could help solve for the waste board not being perfectly level with each of the rails.
A great example of Mesh Bed Leveling implementation is that of the Prusa i3 MK2: https://youtu.be/rYrLT5G-a9I?t=92
I would imagine (just as Mesh Bed Leveling does) that it would factor itself into g-code and make all of its adjustments on the fly.