Looks really promising except:
The 20 person requirement is a bit steep. IMO - You want groups that are forming up to having something that they're workign towards without leaving them completely in the wild to die.
Level 1 should be allowed walls. Walls are like mad importante.
This and very much this.
My character currently has a VSD, M16 suppressed and a SCAR-L suppressed. He's military trained, but looks like an average person. Wears a backward hat, bomber jacket and black cargo pants, surgical mask and bone gloves/sneakers. It's a very memorable look and I've had people call out to me from 100 ft away simply from recognizing the look.
That being said, it's definitely very human to want to be able to protect yourselves and seek out the best equipment possible in this type of situation. You say that people wouldn't be raiding a military base, but take a look at shows like TWD - while fiction in their own right, they absolutely did just that to acquire military grade hardware and then learned how to use it appropriately. In a survival situation it's all about protetection, homesteading and building up until a government can establish order and you don't have to worry about people storming your castle.
Personally, I think it's all about how you present yourself both aesthetically as well as how you present your personality in RP. A desire to get better gear to make your life safer/easier is just human nature.
I'm not really understanding the requirement for the changes from an RP standpoint.
As strictly an RPer with little interest in PvP, the people I play with have spent the last 2 weeks building a realistic compound in Novo and trying to build a settlement. In that time we've taken in about 100 refugees, got standing power to most of the courtyard and settlement, been attacked 6 times, fully raided 3x, held up twice during construction, made friends with mercenary groups, moved 2 other major groups into town, increased the town's population, stood up a proper police force... all through RP.
Is it run and gun in the field? No, but it's society building.. which honestly is exactly what humanity would be doing in this kind of setting. Removing that capability from an RP standpoint seems to be extremely detrimental to the quality and quantity of RP on the server.
As for technical aspects.... yeah, I'm dumb and blind to that.