Nagato's perspective was noble before his immense emotional suffering, and his goals were, in purpose at least, noble even after that. Unlike Orochimaru and Sasuke, for instance.thanks, i see where you're coming from. He didn't have a direct role, but he influenced Nagato's perspective of the ninja world which he took on
Also the chain goes:
JIRAIYA-MINAto-OBito
Visual representation of Jiraiya's direct impact on his grandpupils ethics, even Obito's goals are in essence to prevent suffering.