Skrillex (aka sonny moore) used to be the lead singer of From First to Last, who used to be my favorite band that (with whom I had an unhealthy obessesion), and I noticed that he used to always wear kingdom hearts shirts. In fact, he had stated that he was enormous fan of the series. I dont like dubstep, but when skrillex isnt dropping the bass, his shits super melodic, so itd be super awesome for him to remix dearly beloved or even compose a new kh theme. Before he was a full fledged dubstep artist, he used to just write kind of electronic inspired music, a lot of which was really great, so he has the composing skills. I'd be stoked if he did anything related to kingdom hearts.
edit: hes also a singer, and he did a japanese version of one of his songs he wrote/sang when he was pre-dubstep. so it would completely work if he composed a new theme. just sayin.