To make up for the "workbench gate," I do like the idea of vastly simplified "repair kits" that are little more than gun cleaning kits, exactly like Sirillion suggested. These would be very easy to make (Sirillion's recipe of cloth/iron/oil sounds good to me, maybe even a second recipe that uses gasoline instead of oil).
They would only repair a little bit - like, maybe a faulty quality weapon would have half its durability restored with one repair kit. So they'd be almost useless with higher tiered weapons, and it gives you an incentive to use the workbench/gun parts in mid-to-late game.
But lowering the overall durability has already been talked about, and is pretty much a non-starter. You can look back through this thread, but a lot of it has to do with weapon mods, and what would happen to them if the weapon lost a quality level.
But even if TFP doesn't do any of the above, I'm still liking the ideas that MM has already put forth.
Well, I like the idea of having more recipes for it, but gasoline would not work very well as gasoline is not “fatty” and as such would clean of any oil and make the gun likely to fail faster I think. What could work is tallow which has been used for gun cleaning or other forms of lubrication or cleaning through the times.
https://en.m.wikipedia.org/wiki/Tallow
Adding three tiers of weapon cleaning kits could work well.
1 - Simple Weapons Cleaning Kit
Made with: Cloth, scrap metal and tallow.
2 - Basic Weapons Cleaning Kit
Made with: Cloth, scrap metal and weapons oil.
3 - Advanced Weapons Cleaning Kit
Lootable only, Weapons stores, army camps.
Higher tiers = lower penalties.
When I say penalties to durability it is important not to confuse that with quality degradation. What I mean is that the weapon suffers a loss of max durability, as in the bar no longer go to 100%. Like what happens to health and stamina right now.
No mods are lost or dropped due to that, the mod slots stay just the same, just that the weapon will eventually need a proper cleaning/repair when given the in-the-field treatment enough times as it will “fail” with almost every shot.
This system would mean that if you are careless with the weapon a complete fail when trying to repair it at base would be likely as a repair should calculate based on the level of durability degradation and your skill/perk in doing so and RNG a likely outcome for the gun.
A UI pop up could then present you with a choice. “This weapon is severely damaged and is beyond repair for someone of your skill level. Would you like to salvage the weapon for parts?”
You could then choose to salvage what you can or keep the weapon until your skill increases and try again.