I don't agree with selling him now, mostly because we will be in a massive spot of bother if Chiellini gets injured. He's our 3rd best CB, even if Rugani could surpass him one day. And that's pretty tough to lose with 3 competitions to compete in through the back half of the season.
I'm with you on the Bonucci howler thing, over how terrible our distribution from the back was last season, plus how easy it was to press us into major mistakes. Hopefully it won't be a case of either/or as the winter progresses. To really have a great shot in CL, we need Bonucci back to his 14-15 to 16-17 best.