So was thinking of replayability in the game, and thought that this could be a very good way to up the replayability.
How things work now:
When the realm designer starts a new realm (opening a new file) it generates all of the seeds and assigns them to the tiles around the map. It's then set from here, nothing can be done to change it.

How things could work (with perhaps the smallest change):
Every time a player starts a realm the seeds will be generated.
When the player abandons the realm, and restarts it, a new seed will be generated placing all of the different aspects.

another thought: an option in the menu that says (generate random maps for every realm) could possibly be a good way to manage this.

Having the map seed reset each time the player enters a realm is a good idea

If it were a choice between the two, I'd rather see realm designers be able to make their own maps, but short of that happening; having the seed reset would add replayability.