Ummm... for many of us who role play, settlements are the entire point of the game because they are the rebuilding of the Commonwealth. They serve far more purpose than endless combat, for example, as that leads to nothing (except death, perhaps).
But yes, there have been numerous threads about settlements including suggestions for expansion s and improvements.
Defense value should determine if/when/how often a settlement is attacked. (defense vs. production)
Defense should also determine when/if you get the quests to take out some faction that is harassing said settlement. I mean, seriously, Sanctuary has a defense value well in to triple digits, yet settlers complain that supermutants attack, and all they can do is run and hide? Seriously? And just how many of those supermutants actually even get CLOSE to anything in the settlement, after being riddled with bullets/lasers/missiles???
Same goes for kidnapping. Although, one could argue, that the victim was picked up outside the settlement........
Success/failure of defense should NOT depend on the the PC being there to hold their collective hands....
We should be able to make the houses good as new. I wouldn't mind seeing some new 'components' of buildings, such that we could build pre-war houses, in pristine condition, in various configurations. Or, at the very least, be able to repair the existing homes we cannot scrap, to like-new condition.
Personally, I would like it if there was an option to assign one of the settlers to be a local handyman - someone who can do trivial things as necessary, like making more beds as needed (given indoor floor-space) or perhaps installing basic water pumps. Supplies permitting, of course.
Definitely repairing water pumps and generators, maybe even repairing machine-gun turrets (not the higher-grade turrets, though). Even if there was a cost in caps, materials or effort (like scavenging up some tools) involved, it would make things feel more real and less annoyingly micro-managing.