BioWare did a very smart thing with the squad line-up. I'm glad they brought back the original line-up from ME1, having familiar faces on your crew really helped the game and Shepard face the final chapter of his journey when he knew he had people he could count on.
I also like that you're given the choice to have Ashley/Kaiden on your crew or tell them they'd do more good working alone as a Spectre.
EDI's body was an interesting move because although it gave a new form to EDI, it didn't introduce a new character, it simply gave a body to a character Shepard already knows.
The only new person on your squad is James Vega, who is needed to give an outsiders perspective. But the fact that he's Alliance military makes it a perfect fit because Shepard doesn't need to get to know him, he's had a field transfer to the Normandy and he now works for Shepard, end of story. His purpose was more to be an outsider looking in and making comments about the people you did know from the previous games. He's also a representation of the guilt heavy decisions may end up making on a person since he too has had to make some hard decisions that have cost him and others.
Aside from Vega, there wasn't anyone new (not counting Cortez and Traynor) for Shepard to meet and becomes friends with, for the most part, ME3 was about the connections Shepard had made in previous games and how the connections he made would help him in his journey to unite the galaxy.
Also... prefer Kaiden over Ashley any day... he's a reasonable man while she's... much less reasonable. Down right pushy, in fact.