A S3XY S3RV3R Adds a few Content mods that's also designed to optimize server performance.

Content Mods:

Create: Adds a lot of Vanilla feeling blocks and structures and uses very few new blocks.
Tinkers Construct: This is my favorite mod. It adds a bunch of tools to the game.
Mine Colonies: Make and run NPC towns

Server Things

These mods aim to optimize Minecraft and reduce load on the server. More performance mods to come.

Clumps: Reduce XP lag
Fast Furnace and Fast Workbench: Reduced server load for the respective blocks
FTB Backups: Server Backups
FTB Chunks: Chunk claims
FTB Essentials: Server admin stuff
Performant: Performance improvement mod
Random Patches: Guess.
World Edit: World editing tools

QoL Mods

These make life a little better

Login Shield: Keeps you safe from login lag damage
Fast Leaf Decay: Reduces time it takes leaves to decay
Swing Through Grass: Lets you attack mobs through grass
Quick Homes: Allows users to set homes to teleport to (useful for visiting friends)
Gravestone: puts your Inventory in a gravestone when you die
Nature's Compass: Lets a player search for biomes

This pack has nothing original.