I think, with the recent developments with Ferrari and their engine, and there poor testing form, this years car will be well off the pace - thus forcing Ferrari to switch focus to 2021.
McLaren, again in my opinion, will come good later in the year and out develop RP and Ferrari(if they switch to 2021). I think McLaren will start well but only 4/5th fastest in Australia, and then out develop Ferrari, Renault and RP throughout the year. Also Norris, now in his second year, will do a lot better compared to last year, and whilst not quite on Sainz level I do think he will do better than last year by a fair amount.
That's my reasoning - how it works out we'll see.