Aurelion Sol: Slow on E

One aspect of A.S. that bugs me is the absolute necessity of Rylai's - in my opinion, his character is entirely dependent on the player having a specific item to be effective. In that respect, the upcoming nerf to Rylai's hits this character especially hard. That being said, do any of you think that it would be entirely out of the question to endow his "e" with an innate slow?

Edit - I goofed on the title. I meant to refer to his "w," not his "e"