My ME1 squads would typically be Garrus and Ashley or Garrus and Tali. Of course I'd play with the others from time to time, but not on the Primary Missions.
In ME2, most of the time it would be Garrus and Tali, but given how much richer the field of potential squadmates was, I'd use different people more often. Garrus/Miranda, Garrus/Mordin and Garrus/Thane were common matchups. Miranda/Zaeed, Tali/Grunt, Thane/Tali would happen regularly too. Samara and Kasumi would pop up from time to time. Jacob and Jack had trouble finding their way onto missions. Jack moreso than Jacob. Lots of the time, I'd play Jacks Loyalty mission towards the end and realize upon starting it, I hadn't used her at all since recruitment, as she hadn't filled in any skill points at all.
I'm not sure when it happened, but Garrus somehow became my right hand man in the ME universe. Which is fine with me.