Main reason for not killing Paulie: He would do anything and i mean anything Tony told him to do. Paulie even took a demotion of sorts and never really acted out to much about it other than fucking with Chrissy. He took orders from Bobby B and Sil without a smile on his face but he did what he was told. If Tony absolutely needed something, Paulie would do it before anyone. Chrissy rise in the family should have been underneath Paulie the whole way, i know it was mostly but a time comes where Paulie is cut out. Tony should have NEVER went around Paulie and started sending orders directly through Chrissy. The outcome of curtain feuds with NY would have been much different.