The DLC adds robots you can build, which are actually kind of cool as base defenders or companions, if you’re into that sort of thing (I run usually with the dog). Once you get into the levels beyond say 50, attacks on settlements are pretty common, so you do need some defenses, but you’re right, it doesn’t take much. I’m a dreadful builder, because as you note the interface is terrible. Depending on the settlement, a few strategically placed walls can channel the bad guys, but turret placement seems to be the only really useful decision. And really, simple quantity of turrets usually suffices. It’s tough though when the idiot settlers charge power-armor wearing raiders and engage them in hand to hand combat, so I try to give the settlers decent ranged weapons (goodness knows you have enough of them laying around).
To me, the base building is a huge missed opportunity. The main reason I ignore it is the interface, and the difficulty in doing the simplest things. It would help tremendously if you could, say, create a model/mockup on your PipBoy or a terminal or something and save templates, and then just implement it at each settlement, for example. More simply, if stuff just snapped together better and more intuitively, and if you could get a better top-down or isometric view of the layout. A visible grid would be nice too. I have all these ideas…but inertia gets the better of me.
And don’t get me started on the horribad settler interface. How hard would it be to indicate which food source was worked by which settler? How hard could it be to have a button that simply allocated all unallocated settlers to food production up to the productive limits of your food sources? Why is there no clear indication of WHY a settlement is losing or gaining happiness? And what about Naomi?
OTOH, some of the writing in the game is stellar. Oh, not in the awful main quest; that one is dreck through and through. The side stuff and some of the DLC kicks ass, though, and is really witty. Nuka-World is fabulous; the terminals and side quest stuff are really entertaining, and Far Harbor manages to combine regional jabs (I live in Vermont, so we definitely get the Maine humor) with a bit of Lovecraftian horror and a fairly interesting main plot. Even the basic game has some great side quests and incidental writing. Too bad the main quest is so terrible.
But one thing we can all agree on. The BOS vertibird pilots are, without a doubt, the worse in the world.