Not a bad move at all by Como on Alvaro Morata. Like I always say, I find him overrated.

However...
I think he is just the player for this kind of average teams. He can play more freely without being under high pressure. I guess he will be their best CF option available after this signing.
If De Bruyne avoids injuries, which is a big if, for sure he would be one of the best Serie A players despite the age. I'm not a Napoli supporter but I have to admit that it is a great move, he can really make a difference, especially in the big matches.
I already think the main reason behind signing him is that actually.

Despite the injuries... He is a great team leader in my opinion. His key passes would still be an important contribution.