I think this would be a nice addition along with the battles. I've had some flips/songs come out of the battle rules/samples, but never ended up feeling like putting them into a battle. I would like to be able to focus on one production aspect and have feedback on that with less constraints on samples and instruments.
Is this starting this weekend?
I can't decide whether I think the songs should have a time constraint for that week or any song from whenever is acceptable. Having it be fresh in your mind would help feedback and your ability to change what you want afterwards.
I've seen other methods where if you post a song, you have to give two pieces of feedback, that could be a decent way to make sure it's not too dry one sided stuff.