Not death! But METAL!!!!
I don't have a problem with mord in bot. I think the idea of a non-traditional ADC is a great idea, however Mordekiser is a terrible choice to do this with because his theme is so problematic both for balance and story. Why go the rout of death instead of metal? I think he would be far more interesting if his identity was pushed farther into the realm of metal control instead of death control. There are already a bunch of champions that manipulate/control death we don't need another one. Yes his ult is cool and I think there is a place for it in LOL, but it seems to me that his half-death half-metal theme is his major problem. So, drop the death part and push him further into the realm of metal and melee bot carry. I understand that his ult would no longer be the same but instead of letting him control champions/dragons let him make a straight up metal dragon that he controls just like the normal dragon. If his ult is changed to this there would be a lot of power from the missing current ult would lose but it could be used to balance him into a Lord of Metal instead of a Lord of Death.