How the hell did he not get provided with the right players??
Diego was an amazing signing, not one person on this forum didn't want diego in this team, you included. So saying he was a bad decision is pathetic and your just looking for excuses. The same for Melo, we were all delighted to welcome him. Its typical of juventus fans to completely turn on new signing after 5 or 6 poor performances. Melo and Diego were the right signings, PERIOD.
Yes we could have done with different defensive reinforcements, but if Ciro felt this way then he should have been the one to step up to the plate and ensure the team was built around him. You wouldn't see Hiddink being told who he is going to be signing this summer
And dont feed me that crap about injuries, please, have you even followed Juventus over the last 5 years? I cant remember a month when we haven't been decimated by injuries let alone a season. Injuries happen, you have to deal with them. Ranieri had much worse injury crisis' as pointed out in the above posts. Look at Man U, their whole defence is injured and look how little its effecting them, and that is a much worse crisis than ours.
To answer your question though. Yes, a new coach would get the best out of these players and find a systems for them.
And for the last time Melo isn't a 'regista' and he wont be turned into one, a decent coach would know that and play to his strenghts, it took Prandelli pointing it out to Ferrara to get him to notice that, dont fall into the same trap...