My biggest issue with a number of the "new" stats is that people seem to overvalue them and view them as or close to absolute. I still think these stats don't show context such as poor (IQ) teammates, team injuries, coaching style/effectiveness, high volume vs low volume scorers and how it relates to opponents defensive strategy, diminishing returns for high/low volume scorers, overall defensive stats ...
Will a player play worse on worse team? Will his numbers go down with the lack of support? How about WS and WP on a bad team? You will probably say that it adjusts appropriately but I don't buy or see it.