I’ve been having problems with the traditional overworld portal/water trough/dropper design since moving over to BTU. The pigmen spawn and immediately port over to the nether and are sitting at my bases portal on the nether side and will gank anyone that tries to port through. I’m using single portals with trap doors- if I switch to 5 thick portals, will the pigmen stop porting to the nether right after they spawn?
I haven't heard of any working gold farms. But you don't need coordinates to align portals. An overworld map will show you your corresponding location while you're in the nether. I've been putting a cloned map on the overworld portal, then placing the nether side portal right on top of the marker. Works great.
Not that I know of (but I don't watch many YouTubers). I'll try to explain in detail.
Make a locator map and with it in hand hit "create map" while standing next to the portal in the overworld. Then, clone your map by putting the map and a blank map (doesn't matter which kind) onto a crafting table. Put one of the maps into an item frame on the portal. The map on the portal and the map in your inventory should now have a green arrow, which represents your portal. Go into the nether and look at your map. The green arrow is the overworld portal, the white arrow is your overworld equivalent position. Make the new nether portal where you're standing when the white and green arrows are on top of each other.
If any of that doesn't make sense, let me know and I'll post pictures.
Ok. I just hopped into my current world and did a few shots showing the critical parts. Please excuse the backgrounds, I'm currently in progress on a base in an emptied out ocean monument.
The first is cloning a map. I use classic UI, I don't know what pocket does (I'm playing on an Android device). Notice the recipe book does not show anything in regards to cloning, you have to put in the maps yourself. You can also clone maps on an anvil. The second shows the cloned maps in my hand and in an item frame on the portal. Last image is just after passing through the portal. I moved a little way away so the two arrows have some separation. Notice the maps are fully zoomed out. One pixel on that map represents 16 block in the overworld, and two blocks in the nether. As long as the arrows are right on top of each other, you'll be within two blocks, which has worked great for me. Don't zoom the map at all and moving one block in the nether will move 8 pixels on the map.