Once the sword is finished i'm sure it will not be noticeable. I think the problem people are having is there isn't much to scale it with other than his head and the blade(shoulder guards are always over sized, because they are meant to protect more than just the shoulder, case in point.)
and the cloth is exaggerating the size of his head. Plus you also have to take into account that he wasn't always dead and the armor SHOULD look a little over sized, as its occupant has likely lost about a hundred and fifty pounds of flesh. IMHO hes amazing looking, and carries the weight of his years very well.
You are a very good sculptor Richie. You have not posted anything myself and my little coterie of friends have not liked. You won't fail in this endeavor either.
Now hurry up so i can remove my converted empire general wight king and replace him with this.

(I know I know, art can't be rushed, doesn't make me want it now any less. lol)