I think if I was going for that I'll grab a indictor/guardian kit for the shield and spear umbrella thing. I just don't want it to be too big and people think it's a jack not a caster, if I go down that path.
Currently his body/crotch is a light jack chassis with heavy arms and legs attached.
He's really about the size of a man of war, just with massive forearms.
If I had the $$ right now I think I'd order me some parts and try it. Till then I'll settle on giving this guy some paint.