where did you get the roasted rye? that is unmalted, like roasted barley, correct? you will definitely want some roastiness...you won't get enough from the chocolate malt.
i think it looks like a great recipe. kind of odd hop additions. i know some people like cascade as a bittering hop, but i've never tried it. i don't think it really belongs in an RIS. I'd go with a small amount of some clean, high alpha acid hop for the bittering.
the northern brewer addition at the end is interesting and sounds very tasty.