And 1.13 is released! Plus, I found what I think will be a great new seed with all biomes and almost all structures included in about 2k blocks from spawn. I think I might make it a large biome world to make it even bigger and give more room to maneuver and build and explore. So, definitely much larger than Nyvarld ever was.
We'll see what happens. I've got a lot of projects going on nowadays, but I might have the chance to start working on this a bit this weekend.
Here are some possible tools that can go above and beyond NEI for adding even more flavor to your structures. You just have to wait them to update, and their authors seem pretty active at the moment: