I am not studied in the mythology of mara nature in buddhism but what I have heard would lead me to believe that this personification of subjectively "negative" states of being and modes of action wouldn't be something simply to resist but rather to admit into consciousness and have compassion for, if it is not something that can be separated from buddha nature or the personification of subjectively "positive" states and actions--and I think that non-duality would suggest that this is so. I just don't see attention to the question that non-duality should pose to western metaphysics of dichotomy and opposition and it bugs me.
it seems more to me that the "grasping of evil as such" that Agamben talks about, "leaving no residue" of negativity, while still acting ethically, would be the puzzle that animates a metaphysics of non-duality as well, if it is careful to notice every instance where the dualistic urge arises. it's just too simple to say "resist evil" and "do good" and still hold that all that is is part of the infinite multitude that is the way of the universe.
anyway what I was also thinking is that sitting is not about the avoidance of suffering but about dwelling in the potential to suffer, especially when your legs begin to fall asleep.