Two of the best/biggest fixes to settlements that are needed are scavenging/stores and the entire lack of information available on them. Before building there is nothing to tell you what scavenging does, at least with the stores you get the idea you can buy items at them. It tells you they bring in income but gives zero clue about how much. Is the 600 store going to bring in 2.5x what the 300 one does and how much is that in the first place, 5 caps a day, 50?
Scavenging could be the best mechanic in the game but was ignored. Go to some raider site, clear it then if you have a settlement, scavenging stations and someone assigned to it within range you can press a button and after a given time every item in the cleared site ends up back at the settlement. It's an RPG, not an MMO, dragging junk is a massive grind and considering the still awful interface and missing buttons like transfer all junk between yourself and companions, or my god, a button to god damned lock some items. SO you equip armour/gun/ammo to a companion, press whatever to lock those items. Then take all ignores locked items. How on earth that isn't done I don't know.