Tell me you missed the point of the reply without telling me you missed the point of the reply…
The point was, I don’t have a ton of playtime over you, yet I’m swimming in resources and have everything upgraded, and somehow you don’t. Which means somewhere along the way you must’ve spend those playtime hours in a way that brought very little actual progress.
My method was this: start playing the brand new character, using the equipment they start with. I’d stick to one specific build, and whenever I’d get a higher power weapon that fits that specific build, I would swap. I would only ever buy weapons if I hadn’t found an upgrade in a long long time and I felt I was really falling behind. I wouldn’t upgrade my weapons, ever. I’d reach lvl 30 playing at whatever highest difficulty I had unlocked by that point, and any weapons that I had left after this levelling process that were too low power, I’d sacrifice for Mastery. Over the course of this levelling process, I’d have gotten at least one melee and one ranged weapon to 20 mastery by just playing, and I’d be at around lvl 11 mastery with another one. Then I’d switch to another unlevelled class and do the same. At the end of this process, I’d have at least 8 max mastery weapons plus 8 that were halfway (this was before Arbites and Scum). Then I’d make a new build for each class that explored a playstyle that was different to what I levelled with. And I’d master another set of weapons with that. And so on until I had around 3-5 unique builds per class. Again, not buying weapons, not wasting resources upgrading weapons. Once I felt I had enough of a variety of weapons and builds, I’d work on actually maxing them, i.e. getting full weapon mastery through sacrificing on the weapons that I actually intended to use on that build, fully upgrading those weapons on that character. I’d gamble with Melkbucks (mystery acquisition, not Limited Time Acquisitions, those I reserved for Curios only). And once I had at least one of these “maxed” builds per character, I’d make sure to complete at least one Havoc per week, as that gives you a lot of resources for very little playtime until you get to like Havoc 20+ where multiple attempts may be needed.
Through this process, by the time I fully maxed out all weapons, I had enough of a resource surplus of everything EXCEPT Diamantine to make whatever builds I wanted and fully equip them. Diamantine was the only bottle neck that required several more weeks of Havoc completions to overcome. I’ve never been short on Plasteel and the only times I’d run out of coins was when I was spam buying to get a perfectly rolled weapon from Brunt. That would sometimes eat up to a million coins, if the weapon was extra stubborn.
My guess as to where your inefficiency lies is: you dial down the difficulty too much when you start levelling a new weapon, which not only drastically cuts into how much weapon mastery XP you earn, but also cuts into your resource earnings. I.e. you’ll be spending the equivalent amount of time as if you were playing a higher difficulty but earning way less of everything. Mastey XP in particular is super valuable cause it’s essentially free resources on top of everything you collected. If you then have to max out through sacrificing, that’s coins and plasteel that you’ll be missing later. I basically never play on a lower difficulty than the max while levelling and after, not unless I feel like I’m the reason we’re losing cause I’m underperforming due to unupgraded weapons. I’m also guessing you haven’t been doing Havoc assignments every week, those are a big earner for very little time investment. Even low level Havocs will give you multiple times the resources of a normal map for just one game played per week.