Coming to the crucial question: is it possible to have only one single seed to be used for the mod? It would make the creating of structures much easier, since all the landscapes are always fixed in that case. It enables copying of structures as well, as there would be no landscaping discrepancies, which can be seen between differring seed worlds when copying chunks from one to the other. Also, it would be much more realistic: there is only one Middle-earth! So why would there be different spawns?
Vanilla MC has of course different seeds for every world spawn, as it could be boring if only one single world existed. The aim of the LotR mod however is exactly meant to create one version of Middle-earth, so applying the same vanilla principle is not necessary.
When you go exploring, every discovery is new, unless you have already discovered it yourself. So I guess you mean "re-discovering" locations a second or third time, in case you decide to re-live the world. The first time, if I could get a map where all known locations are mapped by those before me on servers or their private explorations, why would I want to use their detailed map, instead of discovering it myself? Those who have weak will-power or are lazy and cannot resist doing that, will most likely copy a seed and use a given map by others who already discovered that seed, so having one map will not change that. So in my opinion the fact that there is ONE seed makes it more of a familiar experience: everyone will know the same locations, as if you were talking about your home town. Brings people even more together, when they play multi-player. For a single-player, it makes no difference, as who would want to re-discover Middle-earth several times in a row with the city locations all mixed up? The discovery is the biomes, the peoples and cultures, food, animals, etc., rather than the fact that city X or Y is located on that left hill or on that right hill in 6-18 months from now when I would want to play the game again, starting from scratch.. If you actually mean an endless cycle of playing the game with re-created maps that only differ in where the trees, houses, etc. spawn, that seems a bit weird to call it rediscovery, considering that Middle-earth is fixed, given a fixed map, biomes, cultures, etc. The slightly changed location of fixed structures does not add much to that re-living experience in my opinion.
All in all, I would say that I would not worry about "boredom" setting in just because of a fixed seed where the updates come out on. The huge benefit this has is that suddenly you can populate Middle-earth with hundreds, if not thousands of player creations. That should count for something.. 2b1af7f3a8