well thank you for a very clear explanation of your position.
So I have a few thoughts. First one major inflow and outflow you forgot to mention. One is team creation and team retirement. This is generally a net outflow I believe, though I could be wrong.
In a related point, from a macro economic perspective most teams are developing, not established, so I'm not sure how large an effect the "establishing" effect of non monetary inflation is going to be.
Second, I think implicit in your theory of worrying is that the speed of the inflationary/deflationary pressures are faster and stronger than all the feedback mechanisms. Bubbles are dangerous, and if we allowed for massive buzzerbeater loans i could imagine one developing where people bet on the price of a player going up, and it goes up, and people keep somehow irrationally believing it will go up. In reality we don't have that situation, and we have sent the strong signal that we hope to keep prices relatively "constant" meaning a d1 starter should cost roughly the same when we reach equilibrium.
So, how to we determine what the speed of these inflationary and deflationary pressures are, and what the speed of the feedback mechanisms are, and whether we are likely to be in an unstable equilibrium (slow feedback) or a stable one?
I would say that it is not immediately obvious to me one way or the other, but that having mechanisms which are in place to react to these things is better than not having them. I'm not sure what transparency you want us to have with regard to monetary policy... I guess we could try to calculate the total amount of money in the banks of every division and report that as a number and then we could strive to keep that number similar over time... though with player salaries still increasing we are still in the regime where those numbers should be going up over time such that the effecitve player liquidity is similar.
I dont see how adding arena maintenance costs really address the problem as you outlined it. That would simply add an extra outlay, but wouldn't really affect the speed of the feedback, which is what your argument rested upon. It might have made sense if you phase it in just at the rate that you think arena investment will be phased out.. But lets be honest, some inflation is OK. We have inflation in our economy, its in some sense unavoidable when you have a growing economy. What is hurtful and unpleasant is when it happens too fast.. same with deflation... people want their money to be worth the same over the time scale that they are likely to spend all of the money they currently have. They will accept that 3 years from now they will be getting 10x as much and spending 10x as much, they just don't want it to be next week. We are aiming to make sure inflation/deflation happens as little as possible and as slowly as possible. It might be impossible to assure a perfect equilibrium, but our focus should be on keeping a steady level.