Hi Brad Gaston,
That's an interesting thread!
I'm wondering if you already had a look at this article: Creating a Dynamic Ranked Set with Analysis Services | Tableau Software
I found it pretty useful. Let me know if the solutions in there helped you!
If not, I'm sure our community can come up with a fantastic calculation that will help you out.
I actually got an excellent response from Tableau Support. The were able to use Rank_Dense in combination with my LOD calculation that returns the percent of total for what I identified as gaps and strengths. Finally, duplicating that same Rank_Dense calculation and dragging it into the viz in order to sort. I can summarize in a little more detail for others to use.