I think the general idea is good. I’m not sure whether all test-takers will want to have their scores posted in such a way, though. So maybe you should make participation on this list “optional”. In other words, test-takers would have to opt in before they might appear on such a list.
In addition, you also might want to consider that native speaker ESL teachers and forum moderators and coaches might look at the tests for different reasons than ESL students do. So, if you want to post such information, you might want to make at least a small attempt to differentiate between types of users. Otherwise, people might think you are intentionally trying to mislead and misinform.
For example, I took a look one test this morning since a learner had posted a new question in the existing “dumb vs. stupid” thread. Out of the 10 questions in the test, the only question I looked at and answered was the incorrectly written “dumb vs stupid” test sentence. I clicked on the word “dumb”, then checked the answers in order to see whether you have bothered to fix that test yet or not. I see that english-test.net is still getting that one wrong. Don’t you think it’s high time that test sentence was corrected? English-test.net has made no progress whatsoever on getting that test sentence repaired.
How about also starting a “Progress Report” for the correction of errors in the tests?
A good location for discussions of “Errors in the Tests” as well as for a progress report on test editing might be a behind-the scenes forum – which is something I have suggested several times in the past.