So many of us have already felt the terrible lag caused by world generation on the FTB Server. Since this is a known issue with Minecraft 1.6.x our best solution has been to generate a completely new world and then use worldborder and "fill" the entire world. I have been doing this on my local PC on an SSD in an effort to complete the task as quickly as possible. I have been working on this project for a full week now and it is just over half way done.
I am using Biomes O Plenty to generate the world with chocolate dungeons and all the mods we care about so I hope it will bring some interesting variety to exploring.
If you still have items in the "original" world please let us know and we will help you move your stuff over. We will be deleting that world. The newer world we are all living in now with the missing sky can be kept or not, I will leave that up to the users.
Until the Biomes O Plenty world is done generating and fully tested no one needs to think about major changes yet, just know that in another month we may want to just have the one main new world and from there we will add more worlds to adventure in. I am also looking into some new modes of play, I have seen talk of a skyblock type world but uses FTB mods with it. That could be really cool.
Please let me know if you have any questions. Thank you all!
Fir3Marshal, Mr. Chappie, awollangk