compare to total, compare to percent of a main category, compare over periods e.g. month over month to get growth %
If anyone stumbles upon my question looking for an answer, I solved the % of total by persisting a table with totals per period (month, week, etc), then joined that table with the data table from above and used a sum(net_revenue)/max(total_revenue) and a visual filter for the period. It's not the most elegant solution, but it allows for some visual interaction within the nested categories.