Ebony Maw is 3rd in my roster as you can see:

But his prestige is so much lower than my awakened R4's:

So why are my masteries boosting Maw so much more than my other champs? That's like a 2900 pi increase rather than 2200. Is it cause he's a 6*? I'm just wondering if my highest team rating (based of of prestige, not masteries) would be better with Maw or Archangel on my team.