Great work - I am blessed to be a part of this forum and would like to request for an appretice ship under you to learn, contribute and have fun.
On a serious note, this is sort of a mental model I have been building for a while and a couple of things come to my mind :
1). We need to be able to define the floor and ceiling of RoE's and RoCE's and to that extent a mapping of the same for the universe of competitors for each of these companies help a lot. For eg., the RoE and RoCE movement in a fragmented market is much higher than it is is for an oligopolistic/monopolistic market. For eg., in your case it's a function of EPA/sales ratios in the past. We could develop thumb rules similar to what banks use for Return on Assets.
2). One must remember that this is a snapshot, at a point in time. We must look at the sustainability of these metrices on the dash board over a longer time. IMHO, inflection points to be defined quantitatively for each of these businesses - this is a function of the EPA spread and the sustainability of the spread over long. One must remember that a lot of these businesses are still in early years (< 10-12 years of growth) and it's only over 20-25 years can you identify the sustainability of the moat. for eg., for a business like astral, I would be worried if RoIC's go below 25 %, market share dip of more than 5% in a year and EBITDA decline (just representative, not final). Even buffet, has 4-5 key operating metrices that he tracks weekly for each of his businesses - for eg., say underwriting losses in insurance, float growth or Same store sales in retail. In avanti's case, I would track gross margin and asset turns.
3). The EPA spread and the sustainability of it answers the question about the superiority of the business. Like federer in tennis or tendulkar in cricket, it is a high average and consistency of average that indicates a great player.
My only request would be to find out the time dimension - both historical (time lapsed for the business and the time ahead, including key inflection points predicted). Whether in physics, sports or in life, it's longevity that matters.