Arbitrary sorting in reports, using values of data in row or column headers

It is awesome to see greater sorting features released (e.g. https://big.ideas.aha.io/ideas/APP-I-1758). Thank you.

Unfortunately that update doesn't solve one of my sorting needs. I have a timeline report, in which I visualise release names and release dates for several releases of several products from several product lines simultaneously. It is quite a neat report, and one that gets used in high-level monthly reports. The only problem is that I can't sort the rows (with row headers showing product line and product names) in the way I need. On this report, some of my product lines are internal products that are dependencies of some other external products. I would like to put the rows with internal product lines at the top of my report, so the dependencies flow downwards. Unfortunately if the product line names were 'A', 'B', 'C', it turns out 'B' is the internal line. So there's no way I can sort (ascending or descending) to get the row for 'B' at the top of the report. What I need is arbitrary sort order (e.g. using those little grab bars that look like hamburger menus). Even if I were to make a custom field that creates the order I wanted, in other reports I might want to display using another apparently arbitrary order (that makes sense to me). Please add an arbitrary sort order in the report view itself.