Would love to have the option for some basic shapes to indicate non-token items on a map. Scaleable Triangles/Circles would be great. That or some sort of free draw pen could work, too. Would still keep things simple but would allow for adding features to your map.
I do wonder how hard it would be to add diagonal lines, since you are would still be snapping between grid points. Then you could at least outline triangles and non rectangle shapes with the edge tool. But it might completely not be feasible, which I get.