#1 Carlo Ancelotti

Ancelotti is a proven winner and he would, without a doubt have, pardon the Trump quote, "made Arsenal great again". Ancelotti has had extremely successful stints at the greatest of clubs, including Real Madrid, Bayern Munich, Chelsea etc.
The Italian has a ruthless winning mentality about him and would have surely been able to instil that into his troops, something they have lacked oh so much in Wenger's final years.
Ancelotti has a win % of 58.93, which is on the higher side. His man-management skills and tactical expertise are exactly what an Arsenal side lacking any clear direction need. However, with Ancelotti being somewhat of a Champions League specialist, it would have been some task for the Gunners, who will be a part of the Europa League next season as well, to lure him to the Emirates.
According to reports, Ancelotti has taken charge at Napoli, meaning Arsenal missed a trick for sure.