I have some ideas about the roommate note supplement, but I think it makes more sense to have it be a note that’s a farewell, you know? Like we were roommates for a year (or however long you’re roommates at Stanford) and now I’m saying goodbye.
Is that too much of a risk? Am I answering the prompt? I feel like I can just make it more heartfelt and provide context to what I was already going to include, if that makes sense.
Thanks!
If you think that it will “help your roommate, and [Stanford] know you better,” then go for it! 
Write something authentic and revealing.
Disclaimer: Take my advice with a grain of salt. [I</a> was rejected](Stanford Class of 2020 REA Results Thread - #42 by collegederp - Stanford University - College Confidential Forums) by Stanford in the Restrictive Early Action program.
Whatever you feel comfortable writing. It can’t be as much of a risk as other people totally disregarding the prompt altogether and writing something unique that describes themselves (which, for the record, some people also recommend).