Try looking around on the Technic website or the Feed the Beast website.(linked below) Both platforms have packs with many mods, including the ones you are looking for. I hope you find a great pack to play!
The link below will take you to a map called "Chunk Error." This is not necessarily a "start from scratch" map, but it is vanilla and is a map where you have to complete quests to continue on. It is a Minecraft 1.11.x map, relatively new, and I think it is a really fun map to play.
Definitely, try troubleshooting your connection. It sounds like an error with your connection either to the Minecraft servers or just an internet connection issue in general. Are you also having issues with other internet-related tasks?
