I have discovered a new way of efficiently farming pig skins and meat. This method includes Wickerbottom's tentacles, so I can say it's semi-automatic farm. Pigs are fast and easily killed by tentacles, and all we have to do is to pick up whole loot. It saves a lot of time, and it's pretty cheap. For building this farm, I recommend you a Geometric Placement mod.
Guide to Farming Pig Skins and Meat (Step-by-Step)
You have to use pitchwork and prepare a 5x5 area with no turf.
Now, cover the area with cobblestone road. You need 25 of them for a whole place.
Place a lighting rod in the middle of square.
Build a fence around the lighting rod, with double gate on the front side.
Step 4 (Optional)
You can destroy corners of your fence, and build a wooden wall for for a better look.
Build grass wall around the fence, and destroy it (you can use walking cane or hambat). It's important to build only one layer of wall, because you won't be able to build pigs' houses.
Start building houses. You should place them on the corners of black square form Geometric Placement.
When you finish first colum of houses, it should look like this.
Now, you can build second layer of grass wall on finished side. Destrioy it just like previously.
Now you build houses and second layer of walls around your fence, just like in previous steps.
Now, you have to stand on lighting rod texture. Drop your bait here (it can be powder cake, pig skin etc.).
It's time to use your books. Safe amount is 5, but you can use 4 without any problem. If you don't have Bone helm, it's better if you have a something for sanity. It's possible to avoid nightmares attack, but I wouldn't risk. You have to spawn tentacles at evening or night.
Well, it's all. Now you can pick up loot every 4 days, when pigs respawn.
You can use this idea to create a farm with bunnymen.