I'd like to see a new method for fixing Must Not Overlap topology errors for polygons. The idea would be to take the overlap and collapse it down to an average position rather than add or subract the whole area from the parent polygons. For [a simple] example:
I can see this getting exponentially more complex as more overlapping shapes and curves are thrown into the mix, so I'm not sure of the feasibility, but I would find it quite useful.
An example of how I want to use this:
I have a network of lines I'm buffering based on an attribute in order to define subregions of the network. There are many areas where the resulting polygons overlap and none of the existing topology fixes are correct. In places where two lines from separate subregions run parallel, the buffer distance is often greater than the distance between the lines. Thus the lines themselves are encompassed in the overlap and adding, subtracting, or merging the overlap will leave one or both lines either in no region or in an inappropriate region.