Honestly the best use for him is to whack him among one of the khornate infantry units alongside a general and take the two extra attacks. With the big ace/gouged combo that's plus 6 damage as a posed to plus two, no brainier. He'll do more damage like that in a short time than a defensive one.
Even more advantageous when turn counts are taken into consideration.
Kill maim burn, he's Khorne.