However, his more-than-a-couple mediocre years still diminish the overall impact. Also, the offensive standard for outfielders and first basemen is significantly higher than for other positions. At best Murphy is marginal. The fact some other marginals made it in in the past should not lower the bar.
Murphy would be strongly considered if he had played in Atlanta in the 90's instead of in the 80's. You play for a winner, people look fondly on you. You play for those who are out in August, people wonder if you had something to do with the losses. As team leader, it reflects even more strongly on you.