There have been some users that received a post ban and successfully endeavored to have it lifted, then went on to becoming consistently good contributors. The type of structure you propose would definitely have been helpful to them, as all that I recall ended up here on Meta basically asking the same thing you did (just, not as an actual feature request):
I fully read, and followed all of the advice I was given. I'm still banned, what else can I do?
Your feature could have the system set some goals based on your posts to serve as rough suggestions on what to do, and track your progress as you do it. If you have 10 poor quality questions, go fix at least six of them. Progress toward at least (n) quality answers, etc.
This would not fall in any danger of revealing the mechanics of the algorithm. In fact, a reasonably intelligent person could make the exact same suggestions just by looking at your history. All this would provide is structure and encouragement.
People that receive this ban are in the extreme minority. People that successfully work their way out of it are in an even more extreme subset of that minority. This would be helpful, but how many people would it actually help?
If a dev indicates that this would be easily implemented, I'm all for it. However, I don't think it's a justifiable use of resources if an implementation would require any non-trivial amount of work. It's not a bad idea, in fact I think it's rather sharp. But, the devil is in the details, as they say.