My order of preference if it has to be an Italian coach
1. Sarri
2. Inzaghi
3. Ancelotti
4. Montella
Sarri has a poor record in Europe, but Napoli also have mediocre depth compared to us. Here at Juve he could rotate his squad much more, which would allow him to better compete in all competitions. Sarri would probably play Dybala as a false 9 and get the most out of him and our other forwards. I don't know if our results would improve, but he quality of our football definitely would.
Inzaghi has done a great job with Lazio. 4th place and a Coppa Italia final in his first season. This season Lazio have scored more goals than anyone else, which is very impressive. Inzaghi lacks CL experience, but you have to take risks sometimes. Guardiola or Zidane didn't have any experience either when they took over Barca/Real, but they ended up winning multiple CL trophies.
My worry is that Ancelotti is past it. There were rumors from Bayern that he was very unprofessional. Robben said that his 10 year old son receives better training sessions than he did under Ancelotti. There were also rumours that he would smoke in his office while his assistant (his son) would be doing all the drills.
I don't rate Montella. I really hope he doesn't become our coach. The best thing he's done is knock Manure out of the CL, which was admittedly very funny.