When editing dynamic lighting the "re-join as player" is pretty clunky when you need to keep checking your work. A quick view toggle would be a big help here even with fog of war editing. Alternatively or in conjunction, a selectable overlay color for fog of war would be nice. The transparent black is very difficult to make out over darker map or map elements. This color change would only effect the see-through DM view the player's view of fogged areas could easily remain black.
