Wealth in Marathon is better measured by the # of Misriahs and gold items you have, because credits are useless
One of the purposes of money is to be a storage of value: something that can be exchanged for goods in the future
You just can't do this with credits in Marathon.
For example, let's say I want a BR33. I have a million credits. Yet, the only means of acquiring this 3k gun is through schemas (RNG gated) or rook runs.
The strange thing is that the BR33 is an absurdly common weapon in arms lockers. It's not anything especially broken, it's just a good precision rifle. It's really easy to get through rook runs, ignoring the small time commitment. But to go on a rook run, I have to sell my entire inventory which will have other equally scarce items I can't buy from the shop.
This is a common gun and is easy to acquire. Why can't I buy it?
There are a million examples of this. Even with upgrades that cost gold alloy, Traxus' mod selection is limited, so you'll have to keep hoarding mods. God forbid you want a specific purple mod to test something. Good luck!
Same with backpacks with specific perks, or even implants that you can actually buy from the Armory, but they're limited to one per day.
Which is another strange thing. Why are so many things in the armory limited? You can't even buy blue shields more than a couple times. Even blue heals are limited per day, on top of being extremely expensive. Purple implants are limited to one per day, so are blue weapons. Even green mods are limited to 6 a day, like ???
It's like the game is actively trying to get you to hoard as much as possible, yet does not provide the space required for you to keep everything you need. Barters are kept equally inconsistent, which basically forces you in a perpetual loop of scarcity regardless of how many credits you have or how full your vault is.
Whether this is intentional game design (or not), it's really annoying. There are too many items that you cannot liquidate for whatever reason, that are either 1. really common in the actual game or 2. are really rare/inconsistent to get
Regardless of your faction upgrades, credit amount, etc, you will never be able to put together a competitive loadout you like solely with credits and will continually be forced to cram shit in a vault that is just too small. I've been frustrated with this for a while, and it's slowly killing my interest in the game.