What's anyones standard layout for a settlement?
It depends on the settlement size and resources (e.g. water) and my whims.
I usually surround it with a foundation wall, with a steel wall on top of that, then in the centre build a big tower, 6 or 7 foundation blocks high. At the top I put a generator and missile turrets. Mid way up the tower i build an accommodation floor.
I surround a settlement with concrete walls, usually 2 blocks high on average (it depends on variation in ground level, of course) and at least 1 block high at all points. I put turrets at intervals along it.
I have one entrance, which has enough turrets to mince and cook an army of deathclaws. Turrets on the top of the wall either side. Turrets on a platform extending across the top of the entrance (which will be at least 2 blocks high). Turrets on firing platforms built at 1 block height at the sides of the entrance. If size allows, the entrance will be built into the settlement 1 block high for 2 or three block lengths and those will be filled with turrets pointing inwards. Inside the settlement, buildings have an external platform running around them at 1 block height. Along the platform is - you guessed it - turrets. So if an enemy somehow gets into the settlement, it will still be shot by at least a couple of turrets wherever it goes.
10 supermutants led by an overlord attacked one of my smaller defended settlements, one without an entrance tunnel of firing platforms. 1 of them made it a few yards into the settlement.
I'm roleplaying a benign dictator who is founding a country. Top priority is defence - join my country and you will have a safe home.
My basic design for smaller settlements is a single large building inside the outer defensive wall and turrets. Here, for example, is my central market town of County Crossing:
Building size 8x6. 7x6 usable area because one row is used for the stairs.
Ground floor and 1st floor: Shopping centre and gym. 10 shops in 2 rows down the sides. The gym is on the 1st floor, running down the centre as a 7x2 room so there is plenty of airy space for the rows of shops and people can walk under the gym from one row of shops to the other.
2nd floor: Inn and pub. Dorm area with beds for visitors and a lounge area with sofas, tables, chessboards, jukebox and pool table (with cues and balls - it's a bit of a job to get multiple complete sets of balls so in some cases a cue ball will have to be numbered as a stand-in). I might put a bar and restaurant in there, but I'm reluctant to have a shopkeeper on their own all day rather than chatting with others in the shopping centre when business is quiet.
3rd floor: Kitchen, laundry and bathing. Laundry and bathing doesn't work, of course, but it should be part of a permanent settlement. A lift will be used to bring water up from the settlement and a forge (workbench) with a box of bits of steel is there to heat steel to heat the water. I'm going to build a balcony area with lines on it for drying the laundry. I have a massive surplus of purified water production in my settlements so there's enough for laundry and bathing. I'm developing a massive surplus of corn because grain of some kind is a basic staple for life without modern technology since it can be stored without preservation for years. So in time the kitchen in each settlement will have a food store that keeps at least 100 corn.
4th, 5th, 6th and 7th floors: Accomodation. Each floor has 4 3x2 rooms and a 3x3 room. The 3x3 room is for people with children, hence the extra size and an extra (smaller) bed. Each room has a clean double bed and some furniture and decoration.
Each floor has a corridor leading to the emergency exit (labelled with illuminated EXIT signs) that opens onto the fire escape I built on the side of the building, which takes you onto the top of the defensive wall so you're not dependent on the single entrance to get out of the settlement in an emergency. I'll assume the existence of ladders to get from the top of the wall to the ground.
I'm undecided on toilets. The water used in washing and bathing could be piped into a buried lined trench which ran under toilets and out of the settlements, i.e. a mavity powered flushing sewer in the style of Skara Brae and other places. That can't be built in the game, but it's realistic (we have concrete and lead) and the plumbing could be assumed. Or toilets could be built on top of the wall, protruding over the side in the style of a medieval garderobe. Either way, I'd have to assume the existence of some kind of processing facility outside the settlement. A cesspit and leaching field, that sort of thing.
In larger settlements, there are bowling alleys, basketball and football areas, tables and chessboards in the shade of trees, a running track...whatever I can fit in for exercise and recreation. Sanctuary has a library of magazines and a warehouse of power armour and legendary weapons and armour. It also has 3 equipped and powered suits of power armour with heavy weapons in an open shelter, for emergency settlement defence use (as if anything could get through the automated defences).
I'm collecting baseball bats and balls and gloves, but I can't see a way of making any area big enough to play baseball in.
This isn't all built yet - County Crossing is the only completely finished settlement (apart from the toilets). I build each settlement up to heavily defended basic settlements with enough of the essentials, then expand them when I feel like some building and I've acquired enough materials.
I've removed the settlement size limit and installed a few mods for more furniture and decorations and lights and suchlike.
There are 2 things I'm still looking for in a mod - a clean bath and a 100 feet tall statue of myself to stand astride the entrance to Sanctuary.