Can is coming off 2 great seasons, definitely an upgrade over both Sami, Matuidi and Marchi. Bentancur has great potential, needs playing time, if we can give him the minutes we gave to Pogba, i believe he has that potential of being Worldclass..
So yeah, Pjanic, Can with Bentancur is an improvement. Of course in a perfect world, that mid would also have someone like SMS or Fabinho, but I am not sure we can manage, especially if we are getting Martial without selling Dybala..
Can, Martial, Caldara, Spinazzola, Bellerin with only losing a key starter like Alex Sandro and perhaps adding another young midfielder with great tenacity, and defensive skills is a great improvement..