So he carries this massive mace around, dragging a very heavy piece of metal on his body. So what bothers me, is that he doesn't have the same passive as Jhin. I mean, if you build attack speed on Mordekaiser, his animations will look so awkward, which doesn't fit his thematic at all imo. I'd rather see this passive instead:
Passive: Mordekaiser can't gain attack speed, but instead his basic attack swing around, dealing a % of his stats (Surely Attack speed, also maybe AP, AD, armor or health, idk) as damage in an area.
His current animations makes it look like he isn't wearing any metal or heavy mace at all. Feels weird tho.
EDIT: imagine playing him full attack speed + lethal tempo... yeah