Napoli's condition of avoiding being the favourite club is a real advantage for them this season because indeed with this the possibility that they will be in the final is very high considering that currently their bracket is only filled by other Serie A clubs Inter and Milan and one more Benfica. They just need to show their dominance here as they did in the group stage then it will be great for Napoli.
Napolis chance of becoming the favourite clubs this season is greatly threatened by other smaller clubs in their categories just like you mentioned, clubs like benfica will pause a great threat to their success in that season.