You have to admit that Girdershade is a disaster waiting for a group of raiders to find them.
Sierra is certainly not playing with a full deck and Roland is seriously distracted.
In Arefu, they can think Evan King is crazy and paranoid and still be scared stiff.
A bunch of dead Brahmin will do that (something that will critically effect the settlements food supply) and they haven't even found out about the deaths of Lucy and Ian West's parents.
In wiki it also mentions that the settlement of Arefu has shrunk from 30 families to five families (Evan King entry).
On the Caravans, volume of scale is important. If you are too small scale you can't recover from serious setbacks. It is the difference between barely getting by scratching a living out and making enough to set some aside. Of having one guard or having three guards.
I mean I would loved to have some additional quests show up reflecting consequences of your actions.
Getting Deputized by Sheriff Lucas to go after slavers that have taken Maggie or some thing like that.
Or getting a chance of catching Colin Moriarty with his hand in the cookie jar.
Or being asked by Uncle Roe to find and convince Scott "Bean" Wollinski to come back and fix those robots of his because Uncle Roe thinks the town is being scoped out by a raider gang.
Hopefully we will see more of this in Fallout 4 or in a Broken Steel like DLC.
I mean I can see your point about people's reactions being muted, but reading between the lines, the DC wasteland was not recovering.
If the Brotherhood hadn't shown up and made a radical about face in policy, the DC Wasteland would have been nothing but rad scorpions and Super Mutants.
Hopefully Fallout 4 will be more like Fallout New Vegas. The Faction system was a great addition to Fallout.