Randomized Map-specific Ores
Piezo_

Adds two randomly created ores to each world with varying properties depending on the world's seed

Saphire
Ryft77

Adds saphire stuff

Cave explorer tool
SFENCE

Cave explorer tool to use acoustic signals for undergound exploring.

Trucraft
mt-mods

An alternative crafting system done entirely in the world.

Stardust
alerikaisattera

A mineral found at high altitude and items made with it

Technic Grass Clean
1F616EMO

A tool like chainsaw, but cut grass, not tree.

Useful Contraptions
theFox

Some useful contraptions / machines.

Ben's Gear
MissingTextureMan101

Attach tool parts to create new tools and add a whole new layer of strategy to your tool crafting!

Grimoire
monk

Override tool functionality during runtime

Obdy
Sires

Adds some pretty OP tools :)

Strong Wooden Pickaxe
mufigilang

Add strong wooden pickaxe that destroy stone as fast as diamond pickaxe

Ruby Tools+
ReinPlayz

Adds ruby ore, ruby tools, and ruby blocks balanced around diamond-tier gameplay.

Floof
Momo

Add BicBiomeCraft inspired biomes, tools, and items.

Leather Armor
X17

Adds an armor made of leather

Bloodmagic2
mt-mods

The successor to bloodmagic.

Ocular Networks
mt-mods

Draw power from the world, and use it to power machines and tools.

Metatool
SX

Provides API to register node metadata tools along with few useful tools

Brights
_Xenon

Adds bright stuff

Darks
_Xenon

Adds dark stuff

Armor addons
CosyDeer

Additional armors and outfits for 3d armor / Asuna

Banshee
ElCeejo

Adds Banshees, a ghostly mob that haunts pine forests

faction items
Giga_M

add some items to be used as prizes for special events or player achievements

Lakemaker Mod
sunnysideup

A TNT block that makes lakes/bodies of water.

Silver
Jackknife

adds silver ore and tools

Stair Pick
BrandonReese

This is a specialized pick for making stairs.

Too many ores
TeufloV

This adds 53 new ores. But most of them are useless.