Sim Settlements ⭐
This mod by kinggath gives you a completely new way to create settlements by introducing a SimCity like system: zone your settlements for residential, commercial, industrial, and farmland, and your settlers will build their own homes and stores and farm their own crops. Your settlement will grow on its own as NPCs make changes and improvements to their buildings without you having to micromanage them or place every last stick of furniture yourself. Here's a write-up on this imaginative and wonderful mod.
Place Everywhere ⭐
Adding much more flexibility and freedom to your settlements, Place Everywhere lets you move previously static objects like workshop benches and put them wherever you like. You can also build anywhere on your settlement—in trees, in the water, and even inside other objects. Red collision warnings are a thing of the past. Requires the Fallout Script Extender, which you'll find on the final page of this list.
Salvage Beacons ⭐
Tired of carrying all the junk you find in the world all the way back to your settlements? This mod gets your settlers to lend a hand. Craft salvage beacons at your chemistry station, and when you're out exploring and your pockets get full, just fill a container with your junk, drop a beacon on it, and your settlers will come and collect everything for you. They'll then place it in your workbench, saving you the trip.
Workshop Synth Production ⭐
With so much focus on building things in Fallout 4, it's surprising Bethesda didn't think of this themselves. This mod will let you craft your own settlers in your workshop. Synthetic settlers. Switch off your radio beacon, because now you can populate your various outposts with (hopefully) friendly Synths. DIY just jumped to the next level.
Wall Pass-Through Power Conduits ⭐
Running power lines around your Fallout 4 settlements just got a lot easier with this useful mod created by Daedragon. Since you're building with crummy, rusty metal walls full of holes, or wooden ones that would be a snap to make holes in, why can't you run power lines right through them? This mod adds conduits you can snap into place on the back of standard ones to allow power lines to pass through your walls. Works with your roof, too.
Need to get away from your crowds of dead-eyed settlers for a little quiet time? Basement Living adds 10 standalone basements and bunkers to give you your very own cozy retreat. You can attach a basement to any settlement you wish, and each comes with a fusebox that provides 100 power, and a workbench so you can decorate it however you like.
You don't have to stick to the settlements Fallout 4 gives you. Now you can make your own pretty much wherever you like. This mod adds campsites which can be placed in the area of your choosing, and if you're happy with the location you can turn it into a fully-functioning settlement. You can build as many as 10 new settlements, and dismantle them as well.
Faction Housing Overhaul
It's nice that factions give you living quarters when you join them, but their offerings are typically not somewhere you'd really want to spend much time. These mods turn those faction dumps into more beautiful and spacious living quarters with workbenches, a gym, lovely decorations and plenty of extra storage space. It's available for Vault 81, Prydwen, the Railroad, the Castle, and The Institute.
If you've got the Contraptions Workshop DLC for Fallout 4, you'll definitely want this mod which vastly improves your settlements' factories. It adds a number of commonsense features, like conveyor belts that will take junk directly from your workshop's inventory and deposit completed items back into it. It also gives you new machines like looms for creating Vault outfits and faction gear, a power armor forge, a distillery for manufacturing cola and booze, and forges for melee and fist weapons. There's even an auto-butcher, for breaking down creatures (and people) into meat, bone, and leather.
The settlers who answer to your radio beacon are typically a bit... well, dull. Most of them are dressed roughly alike, and they can be hard to tell apart without personally dressing them up differently. This mod adds over 150 new settlers so the vacant-eyed corn-growers who arrive on your turf will have a bit more personality. Another mod, Don't Call Me Settler, will give them unique names as well.
In case you want to tweak or change your character's looks after you leave your home at the beginning of Fallout 4, you can do so at a plastic surgeon. This mod gives you the option of doing it from any of your settlements as well, by adding a mirror to your workshop. Simply place the mirror on any wall you want, and using it will bring up the menu that allows you to change your appearance.
Decorating your settlement can be irksome, and even after carefully placing loot items on shelves or tables they can and probably will be knocked over later by some clumsy settler or companion (or you). This mod not only makes placement of items easier (loot items are now movable just like static objects when using the workshop menu), but lets you lock them in place so they can't be toppled. Perfect.
Higher Settlement Budget
The size of your Fallout 4 settlements is pretty severely restricted: they can only get so big and use so many objects. That stinks if you're building a big 'ol base and suddenly have to stop. The Higher Settlement Budget mod fixes this, though keep in mind adding more object may lessen performance or even crash your game.
Homemaker gives you more options for your settlements. It includes two new plantable crops, more walls and fences, 30 new types of lights, and new containers like ammo boxes and lockers. You can even use meat bags, if you like storing your extra supplies in bags of meat. Some do.