Unity Fee
Based on Unity Prices Plans I created some graphs for better visualisation new pricing plans per one Pro/Enterprice seat and Free version monthly. I tried cover most cases therefore set the Installs in the range from 10k to 100 mln. Based on your suggestions the calculations considered both the overall and accumulative cases.
-If u wanna earn some money you dont wanna be bellow the blue line, therefore in most scenarios Unity force developers to buy an pay subscription, add more ads or add more microtransaction from game to achieve more revenue per Install.
-The installTiersLevels in most cases are unpracticable.
Any questions? Feel free to ask on mateuszwallace@gmail.com.
Overall
Accumulative