There's many modpacks that have performance mods in them but they're either bloated with other stuff or they only have a few you could just add yourself. This modpack is a all-in-one pack of the best FPS mods

A horror modpack that overhauls the vanilla game to be scarier & more difficult - mobs are more dangerous, nights are unrelenting, theirs terrifying monsters lurking behind the fog, in the depths of caves - waiting for you...

HyCraft is an old Modpack from 2014 revitalized for newer versions of Minecraft. It's a modpack emphasizing exploration, combat, challenges, and progression in a balanced but chaotic way!