If Bernal's back is okay he should be the top favourite. Those mountain stages in the last nine days are perfect for him. He will lose something in the time trials, but there's ample opportunity to make that up.
Yates is still somewhat doubtful over three weeks. The mountains in Italy are higher and longer than those in Spain.
Evenepoel should realistically not be among the top favorites, but on the other hand he was impressive in Burgos last year, so it's not unthinkable. However after that heavy injury and without competition it would be abnormal if he could win this, also because it's only his first GT.
Landa looked like a future Giro winner a few years ago, and he's here now as the leader of a strong team. He's underhyped at the moment. If he can avoid his usual time loss in the first half of a GT he can become a contender in the high mountains.
Vlasov is another question mark. He looked very strong in several one day and one week races, but he still has everything to prove in a GT.
Nibali seems to be past his peak as a GT rider, although you can't completely write him off. He still has the experience and the tactics, and maybe he's been hiding himself.
Other than those six there are guys like Soler, Buchmann, Bennett and Carthy, but they'd probably settle for a place of honour. It's funny how Hndley and Almeida are hardly among the favorites, in spite of finishing second and third last year.