Specify symbol values for proportional symbol legends
Currently once you get your symbol set, the only real option to control the legend for Proportional Symbols symbology is the number of classes. You do not have control over the values shown in the legend, nor do they reflect the range of your data well.
In my map, I have values ranging up to 450, so I've set both maximums on the histogram to 500. This gets my map looking the way I want it, but the legend, no matter how many classes (or maybe sampling values is a better term), only shows values up to 100, which isn't very useful, and I can't figure out why it maxes out there.
What I'm picturing is more of a table interface that combines elements of Unique Values and Graduated Symbols. It would let you manually add values similar to Unique Values...
...but automatically size your template (based on those values) and order them like Graduated Symbols:
That way, in my case, I might create a legend with symbols representing 50, 250, and 500, which is more in line with the range of the data, and I get to control and mess with it. My only option right now is to eyeball those sizes (or create a fake feature) and create the legend manually.
The same lack of functionality exists when varying symbology by a secondary (size) attribute - aside from a separate issue impacting the scaling of outlines, there is no evident way to set even the number of classes, much less the values of said classes.
