Hmm.. not a fan of the large square background in your designs. It shouts "cheap" to me (no offense meant).
And you don't have any other message other than "King of Everything"? That message doesn't also sit well with me.
Yes, I think you also need to use other font, one of the rule in shirt design is "Readability" so you should use fonts that can easily be read by someone within 20 feet.. just my opinion.