So I just now ventured into a snapshot of the 1.13 version and generated a world with the same seed as our Empire. The world looks pretty much identical to ours. I think the main differences are only the ones which are already introduced before 1.13. There are however some upcoming changes that are planned in 1.13 which are not active in the snapshots yet, such as Magma blocks in underwater ravines and coral reefs in ocean biomes.
So since the 1.13 is generally quite similar but introduces some changes, I made the decision to wait with the regeneration of the empty empire lots until the 1.13 release so that we get those changes as well, specially because the rest of the world will most likely fit in 100%.
If the edges between occupied lots (which will stay the same) and empty lots (which I will then re-generate with 1.13 version) will be seamless, I will consider to do the same for the kingdom, possibly also Aether.
We can consider regenerating the darklands as well, specially to have the corals more accessible, but I am not 100% decided on that one yet. I will first do the general server upgrade, then the empty lot reset and then we can decide if it’s worth it to regenerate the darklands as well with some time to prepare for it to salvage existing structures such as rails etc.
Hope that is fine with everyone.