I agree with you You_Too, it would be a lot of work to rotoscope the sabers to look theater correct...maybe not so much for the Luke and Ben scene perhaps, but the Vader and Ben scene, would be a massive untertaking. It could be done, but does Harmy (or anyone else) really want to put that much work into those selected scenes?
Perhaps team -1 will indeed be able to expose the true theater look of all of the saber scenes, only a bit more time will tell...we can only hope so!
You mentioned the SE lightsabers, what did they look like? Where those the ones that were incorrectly colored?
dlvh