I have only lightly tracked this, since I'm not American, but I understand that there's now a strong right-wing focus in 60 Minutes, is that correct?

Ross Douthat's Wikipedia page makes him sound strongly religiously conservative: anti-abortion, a book title 'a nation of heretics', publications like 'Believe: Why Everyone Should Be Religious' and 'The Decadent Society: How We Became the Victims of Our Own Success'.

Americans who know who he is more than a Wikipedia profile: is this a positive move for neutral, informed journalism, or is it likely aligned with presenting specific agendas?

The latter, and/or cultivating favor with certain people in positions of power.

I haven’t been paying that much attention, but IIRC CBS was acquired relatively recently by someone with right wing associations.