Verratti was the more obvious signing for sure. However his career has turned out disappointingly so far, especially for the Azzurri. I just checked and he has played less than 2 full games for Italy in a tournament (World Cup 2014).
You must watch a lot of PSG games or something for him to impress. I only watch them sometimes in the latter stages of CL and he is less available than Neymar

I think I've seen him once in the CL knockouts in the last 4 or so years. But yeah, he's good when he plays
But you like them fragile, luxury players *cough* Zaniolo *cough*
Barella is legit though and in his short career I've seen more from him for the Azzurri than from Verratti.