You mean, redlining? Where, for example, you've drawn a horse and you don't think the legs look right. So someone goes over it in red to show you how to make them look correct?
I think a subsection for that would be cool. I know I've often seen people ask what they can do better, but I hesitate to redline because a lot of people take offense to it. So unless someone straight out asks for it, I wouldn't do it. But to have a section for people who want real critique and help would be nice. A lot of the time when people ask for critique in the creativity section, they don't really mean it, and then it turns into a big mess.
I'm pretty sure you're talking about on the oekaki though. But whether on there or just a section for it in creativity I'd certainly like to see it.