I like a mix of both, with it being weighted towards "new," so this line up is pretty exciting for me. With returning characters, there's always the chance the companion returning is someone I am not particularly interested in seeing again and it makes me pessimistic. To be fair, though, when they've brought back someone I didn't particularly care if I saw again (Anders, Merrill), they were interesting enough that I wound up being glad to have them. Still, if it's ~all new~ people, I have an easier time getting excited than when I'm thinking "blaaaaah, I don't give a crap about Leliana" or whatever.
That said, I am pleased Varric is returning. 