I have used the great mod Middle Earth BC by billw as a basis for my buildings. Thanks for letting me share.
This world save was done using Better Continents version 0.6.4.
My Lord of the Rings based buildings are all unique builds loosly based on either the films or - in case of Rivendell - a mix with drawings by the professor.
I have tried to create something recognizable while still optimizing the builds for playing.
Since all was done in vanilla Valheim with only a couple of quality of life mods (TorchesEternal) enabled - which are not necessary - and Better Continents - needed for the Middle Earth seed to work - the surroundings are mostly left untouched. I have found that my markings on the map are not transferring, so I took a screenshot with the marked locations.

All building was done in creative mode, but with no other mod, so the builds should work without anything else enabled. If you run into
trouble, try installing Jotunn, since I had that running when I did the building.

Changelog
- V2 is updated to work with Hearth & Home, including kitchen updates wherever possible.
- Slightly updated builds using the new stuff from H&H.
- Added a semi hidden treasure room at Helms Deep.
- I removed all personal chests as it turned out no one could use those.
- The Mines of Moria added - A huge thanks you to Captain Chaos who invited me to see his world and allowed me to use his ideas.
- There is now a hideaway on the highest mountain. Nothing to do with Lord of the Rings - just because ;-)
- Added a picture of my inworld map with marked locations.
- Per user request V2 comes in two versions: One that has no stocks and the "loot" version is mostly fully stocked.
- The ZIP-file now also includes a pictore of the inworld map with all locations.


To make sure this works (as I have never done this before) I quote billw for the installation bit:

Installation

• Backup your worlds and characters
• Ensure you have the latest version of Better Continents installed (including its dependencies)
• Download this world save
• Unzip it into your worlds directory, which is located at C:\Users\<user name>\AppData\LocalLow\IronGate\Valheim\worlds
• Run the game and you should see MiddleEarthBC listed in the worlds list, so just load it like normal and play!
  

Server Installation

• Backup your worlds and characters
• Ensure you have the latest version of Better Continents installed (including its dependencies)
• Download this world save
• Unzip it anywhere you want
• Stop your server
• Make sure you have "enabled mods" on your server. How you do this will depend on your server provider. Their documentation should explain it. If you have full FTP access then you might need to upload BepInEx and configure it to be used by the server (see BepInEx Valheim documentation).
• Upload the world files to your server. This is probably be by FTP, but depends on your server provider. They should clearly indicate where to upload worlds to, if they are half way decent
• Upload the Better Continents dll from the mod to the server. Again, probably by FTP. It goes in the BepInEx\plugins directory as normal
• Modify your server to point at this world instead. How this is done again is dependent on the server provider, but an example is here. Enter MiddleEarthBC as the world name or save name, or however it is referred to by your provider
• Start your server again, it should launch MiddleEarthBC
• All clients MUST have the same version of Better Continents as the server, that is the only requirement.
  None of the Better Continents config settings have any affect on already created worlds, so don't worry about them. On connection to the server the world settings are sent to the client, and the version is verified (since 0.4.3). You can still connect to servers that don't use the mod at all, or that are running a world that doesn't use it, the version check is skipped entirely in these cases.