He's definitely not average. Not a world beater, but a very good player. And judging him based on how Fiorentina finished last season is ridiculous. Using that logic, we shouldn't be asking anywhere near 50 million for Perisic since we finished 7th in a shitty Serie A.
We've had a number of important players from teams that are below Fiorentina in the past like Icardi, T. Motta, Milito, Palacio. It's not as if T. Motta was considered a world beater by anyone here when we bought him. I'd actually put Vecino similar to him in terms of how valued they were before moving to Inter.