A great coach who is full of experience can certainly raise the enthusiasm of a team to perform better. Napoli need to get a coach like that regardless of who they want to sign, but I definitely agree that Conte is the one who deserves the job.
Gian Piero Gasperini has been Atalanta coach since 2016 and recently won the Europa League title. That is the only title Gian Piero Gasperini has won in Serie A since he coached Atalanta, so I don't think Gasperini is the most desirable coach to take charge of Napoli next season. Conte is much more convincing for the job, but I don't understand the terms or some kind of agreement in question.
Coaches have an important role for a team and coaches are the first people who try to create strategies when they compete. Even though the quality of the players is also very important, if the coach is unable to enable the players to develop their skills while playing, the players will never get the opportunity to develop by giving the team a win. Whether it's appropriate or not, let's see how Napoli tries to put their trust in him and maybe next season it will be clearer.
As you said, Gian Piero Gasperini is a coach who has not made a good history in his coaching chair and this is the first time he has succeeded in achieving the best title with Atalanta. So giving him the opportunity to coach a big team may not necessarily be able to be carried out well and on the other hand I also agree with you that Conte is much more promising.