Here is an open issue indicating a possible direction for this if anyone wants to contribute:
https://github.com/GoldenCheetah/GoldenCheetah/issues/3535
For the moment there are some minor changes in v3.6 to reduce the number of charts: Histogram chart allows to select the data series from the reveal controls enabled when hovering the cursor over the top of the chart, this allows to have just one Histogram chart and quickly switch between Power, HR, Speed, Cadence, etc. instead of having 4 or more separate charts. The same applies to CP chart.
The ability to easily reorder the charts allows to put the frequently used on the left for easy access too.