A suggestion stems necessarily from a complaint,to which i am not obligated to write a detailed implementation of it as you did.
Money loses its value from the diminishing need for it, and item permanency does that exactly even if so little.
buying defends for that amount of money, which requires absolutely nothing , when they can do it for much cheaper (supposing that players are min-maxing the game), is a sign of money inflation , that riches no longer care about (money), and no one can deny this supposing they read torn threads once in a while.
That would be a part of the fix, having to buy items consistently can be a good way to justify the need for more money. What i can do with all the wealth if i had the best items (forever).
I know you've invested a lot of your time in the game, but i would love to see a counter argument to my suggestion rather than defending your commitment to this game.
I am not saying the game is bad, but the economy it is built on have to be changed.