The Nets won 42 games last season with a different All-Star PG. Maybe they win a couple of more games this season, but Kyrie isn't going to take that team over the top without some major improvements from their role players. People already thought they overachieved last season; overachieving isn't exactly Kyrie's forte.
Oh I don't think they are contender, but I do expect their younger players to keep developing, Irving is better than Russell, and they added Jordan, Temple, and Prince who I think will add more than Carroll and Crabbe. Thus, I would expect them to win more games than they did last year and have a real shot at hosting the 1st round and winning a playoff series. I'd be pretty surprised if they were a conference finals type team as I do think Milwaukee, Philadelphia, and Indiana are better, Toronto certainly would be if Leonard returned (and probably isn't much behind even if Leonard does leave), and a team like the Celtics (depending on how the rest of free agency shakes out) could be better as well. The East is shaping up to be pretty darn interesting as Miami will be improved, Orlando should keep progressing, Detroit should be about the same or a little better, and I expect Atlanta to make a pretty good jump as Young and Collins keep growing. No longer is the East the patsy, especially if Leonard returns to the Raptors.