Okay, let's not go revisionist wild here.
First, JVR for Schenn was, at the time, a completely fair deal. At the time, JvR was a recent top 5 pick with huge question marks regarding his consistency and physicality and Luke Schenn was a recent top 5 pick with huge question marks about his skating and offensive ceiling.
JVR became and Olympian in Toronto, he wasn't one in Philly.
Second, no one could have predicted that we'd get Cody Franson for Brett Lebda. Anyone here who says they could have predicted it has a better dealer than Rob Ford.
Third, at the time of the trade, Blacker and Holland were viewed as prospects of comparative value in comparative situations. Holland was in an Anaheim system with a backlog of forward talent and many hockey prospect columnists considered this his "make or break" year. Blacker was passed on the defensive depth chart in Toronto by several younger prospects in Toronto and had been lost in the shuffle. Did Holland have more value? Yes, largely because of his AHL play. But in no way did this appear to be some sort of outlandish steal at the time. As with the JVR-Schenn deal, subsequent events have inflated Toronto's return from the trade.
Aside from the Lebda-Franson deal, none of the deals you listed were anything other than the Leafs paying market value for the worth of an asset at the time of the trade.