This pack is designed with Hardcore players in mind, though can be played on other difficulties for players that want a more "casual" Hardcore survival experience. Tech progression has been pushed to post nether and end tech requires trips to the end, and killing the Ender Dragon.
Removing mods from this pack will inherently break the recipes! Adding mods will probably break the progression.
Hostile Worlds by Corosus has been disabled server side. While this mod is used to ramp up the difficulty of SSP after a certain period of time has gone by, it is very unfair for use on a standing server. Once the invaders spawn, new players will not have a chance to get any sort of defenses set up. This mod should only be enabled for Hardcore Challenge servers, you have been warned.
I have supplied a set of arguments with the server download as recommended for running the server.