When I first decided to start my Adept playthrough of Mass Effect 2 way back when, I thought to myself, "sperez2012, what would be more fun than being a master Biotic?" I answered myself with, "HAVING TWO OTHER BIOTIC SQUADMATES, THAT'S WHAT!"
So I recruited Jack and Samara as fast as I could.
I distinctly remember using them on the Collector Ship mission due to the large amount of organic enemies. Between me using Singularity for crowd control, Jack Shockwaving through multiple Husks, and Samara using Pull while I use Throw, dispatching enemies was never easier.
Also, (not nearly as fun, but funny), while playing Soldier I would take Garrus and Grunt and we'd just Concussive Shot everything.
So, what are the Wiki's favorite class and squad pairings, and for what reason? You also have the option of naming mission-specific squad pairings, like when I do "Legion: A House Divided" I always take Tali along so I have my own army of Geth as well because of Legion's and Tali's Area AI Hacking.