In chapter 5 of Pirkei Avos, it states (from Chabad.org):
יט. כל מי שיש בידו שלושה דברים הללו הוא מתלמידיו של אברהם אבינו. ושלושה דברים אחרים הוא מתלמידיו של בלעם הרשע.
19. Whoever possesses the following three traits is of the disciples of our father Abraham; and whoever possesses the opposite three traits is of the disciples of the wicked Balaam
The three traits are: a good/evil eye, a meek/haughty soul, and a humble/gross spirit.
There must be a tens of people the Mishna could have picked to represent these traits, on either side, and some of them would seem to be better pairs than Avraham/Bilaam. Just coming to mind is Avraham/Nimrod, Yaakov/Eisav, Moshe/Pharoah, or even Moshe/Bilaam. So I'm wondering, why Avraham and Bilaam? Are they considered the epitome of these traits, and is that the only reason that they are paired?
More importantly, do any of the classical commentaries discuss this?