The World Cross PVP matching system for Team PVP should revise their algorithm to match players not only based on ranks but also in accordance with the characters selected.  The latter should be contingent on normalized character win rates and for this to be appropriate the character win/lose data set should be reset every month.

Because, character balancing is a problem.
Or rather, character balancing was never looked at in the context of WXPVP.  And based on this alone why would the 2nd paragraph of this post be brought into picture at all.