First of all thank u for the feedback i like to see more nerds around.
Now before i adress each thing you said, let me just say that english is not my native language so i think a lot of confusions were caused by poor word choices and i'm sorry about that xD
1. What i meant by "law" is that in this system, with those concessions, those equations will always be true.
1. I couldn't make it not supply dependent because supply increases with cost at each supply you buy. Therefore i needed to factor that increase. It doesn't really matter if the supply has 45 or 90 because as i said, I'm not restricting the variables to integers, so there is no imperfect supply usage.
2. I don't think i understood what you ment by exogenous, as I'm reconsidering the new "ratio" and new income on each supply, as the number of spawners and extractors change. There are no outside variables in this system.
3. I did consider the flat 30 when i said the initial spawner value is 54 (flat 30 + 24 initial spawners)
5. I'm still at introduction to macroeconomics, but maybe macroeconomics wont apply to this game. To further investigate, as i mentioned, I'm working on a simulator. I'll share some preliminar results I got from it. The simulator considers time (building time for extractors and spawners too) and all costs that are in the game. I'll attach it on this post. To make it a fair comparison, I got the simulator to make only slowlings and extractors. It can deal with imperfect supply - it will always get bellow 4 before buying the next supply. I ran the simulation for a milion seconds and this is what i got for income (y axis) by time (x axis):
https://imgur.com/e9vewLDThis sure doesn't look like a exponential curve, but to confirm it, I'll make the y axis in log scale:
https://imgur.com/YBOwnAtI can be wrong as i might be lacking some information or something, but i think that given that the simulator is working properly (I believe it is) that curve is not exponential.
8. What i meant by accumulated mineral bank is the lifetime income - mineral bank at the end + all spent minerals.
Unfortunately i don't have knowledge on curve fitting, but if want to give it a try i would be happy to check it out. In any case i can ask a friend for help - he is studying engineering and is nerdier than me so i guess he can do it.