RatPack 2

Ratpack 2 is primarily designed for smaller group play.
It has a few mods in basically every category.

For those who are more interested in the technological aspect, we have things like:
Create, a very in depth mod that uses Rotational Force in order to generate kinetic energy. Allows things like, fully functional elevators powered by waterwheels/windmills. A fully automatic crafting system that allows you to create machining lines.

For those interested in the magic side of things:
Mana and Artifice, the spiritual successor to Ars Magica 2, Thaumcraft, Witchery, exc.
It's a fully in depth and incredibly well made magic mod allowing you to custom make spells, join factions, become stupidly powerful via enhancing yourself with rituals.

These are only 2 of the mods, however they are admittedly the biggest of them.
There is also plentiful amounts of exploration content, and the updated end to require 12 unique eyes.
This allows for a longer playtime and general server enjoyment window.

Overall I think it's fairly balanced and is all about being able to do whatever your heart fancies.