Why: To help with larger-scale planning that blue-prints aren't quite good for as well as keep everyone focused on different goals.
How this would work:
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Different Maps are listed on the left. Each is toggle-able individually ("Resource Allocation" map is toggled off in image)
Drawing tools on top. (line, circle, point, square, arrow)
(not shown in image is an add new map button).
Maps would be global (or shared via the existing blueprint system).
Thoughts?
Edit: Some formatting changes to make the suggestion better.