Why I disagree...
1. If Murph had put up those same 44 WAR (46.5 bWAR) while playing much of his career in New York, Boston, Chicago, or LA, he would have probably been a first or second ballot Hall of Famer. He is penalized for playing in what was at the time a smaller market. If his numbers are good enough to get him in as a big market player, they are good enough period.
2. Harold Baines, Jim Rice, Tony Oliva, Ted Simmons. Those guys are all in the Hall of Fame, in spite of similar WAR numbers. None of them was ever a top 2-3 player in MLB. Maybe Oliva in his peak which was before my time. Murphy was one of the top players in the game from 1982 through 1987. You can make the argument that you shouldn't base a candidate's worthiness on the lowest common denominator, but why does our guy have to be the one to get the shaft if we're letting in unworthy candidates?
3. Character. We are clearly excluding players with deserving qualifications due to character concerns. Pete Rose, Barry Bonds, Roger Clemens and probably Curt Schilling would all be in if it was purely a numbers game. If we are going to hold people out because they're "bad", shouldn't being exceptionally "good" give a boost to fringe candidates?
If we're going to use subjective criteria, there is no real argument for keeping Murphy out. If the decision criteria are objective, like a minimum number of WAR, then get rid of all the guys below that count and let Bonds, Rose, Clemens, etc. in.