I have been constantly working on Make2d for the Rhino 6.0 WIP and believe we have made great advances from V5 and the product is ready for prime time.
Lately I have worked to improve the performance both in the large single polysurface case and the case of many objects. Most of this involved spreading the workload over multiple threads. I have also tweaked the progress reporting feedback that the command offers so the progress bar isn't stuck at 0% or 99% as often as before.
I know there are features that people would like to have that have not been added. I think the top of this list is getting a closed curve from the intersection with clipping planes. These closed curves can then optionally make occluding geometry so cut objects appear capped in Make2D. Also the 2D-closed regions could be made hatched.
However, first I want to know what the problems are with the existing features. So please give it a try and let me know.