Board Thread:General Discussion/@comment-187.22.238.221-20150810184156/@comment-6881629-20150811113144

The only followers with what i would think of as utility are from mods, things like crafting items for you.

For strong followers i'd say Frea, and the Dawnguard Ingjard, Durak and Celann they have no level cap but you have to have their dlc and get a few quests into the story. The dlc followers do seem to have more perks than base game followers.

The two mercanarysJenassa and Teldryn Sero are easy to get (Teldryn is dlc), they both have more personality than your basic npc merc.