Here’s a preview of a new feature that will appear in the 1.4 release: 
Viz Deconstruction
Your overall chart calc time is slow, but where in the chart is that time being spent? Click the for a Viz and you’ll get a breakdown of calc time per expression. (highlights added in the example below).
Here’s another use case. This chart has seven Dimensions resulting in 7M+ rows and 8+ seconds of calc per Measure.
I’m thinking for the sake of better response time and a more usable chart, I might get by with a lower level of detail. I can use the Dim checkboxes to remove some Dimensions and QSDA will recalculate for me.
Ooooh.