Personally I'm hoping Wrex, Ash and Liara all come back together at some point so you can have a proper reunion.
I'm really hoping for Garrus to be on your team if he survived, Mass Effect without Garrus just wouldn't feel right to me. I liked him in ME1 when a lot of other people didn't, but in ME2 he was such a badass that I'd hate for Bioware to drop him now just because he might have died in the suicide mission. The team members I really hope return are:
2) Liara (my FemShep's lover
3) Ashley (my MaleShep's lover, whom he cheated on with Miranda)
The rest I don't care about so much, but it would be nice to have them if possible. It would be great if Ashley and Miranda were on your team at the same time and secretly dating both of them, but I have a feeling that sort of relationship complexity wont make it into ME3.
That being said, I intend to do another play-through of both games with a new character at some point where everyone dies on the suicide mission except for the one or two team members I need for Shepard to survive. I also intend to do one where everyone survives in order to get that achievement.