This is a good analysis, particularly of the bottom levels. I never tried that because I do not want to overbuild due to cost.
The drawback to your approach is that you will have spent $256,000 to make $6400 per week, a return of 2.5% per game, while I have spent $80,000 to make $4000 per week, a return of 5% per game. In a game of limited resources, I prefer my approach.
If one is to buy and sell a lot like Boss, those profits can fund the overbuilding without any negative carrying cost consequences. It simply requires more time to churn players, something I find tedious.
So I think there needs to be two versions of 'How to Build Your Arena' One for people who have the time and inclination to accumulate trading profits, and one for players who only want to look in on BB for a few minutes several times per week.