Overwatch's Reinhardt's what Mordekaiser's supposed to be
Simply put a Badass in heavy Armor and large weapon leading the charge to bring desolation and misery to his enemies while walking all over them if they're unlucky enough to stand in his way. That's what Morde should have been actually; Someone you can't ignore in teamfights as he'll simply tear you to shreds if you're not able to get him out of your face. Think something like Nasus but with less utility but a more easily access to damage and survivability.
He's the goddamn master of Metal, maybe he just should be the one wanting to simply walk into Mordor...I mean the enemy team.
And many more. I think we got that covered.