I’m a bit biased because the first manga volume I read was way above my level. (I used it as a means to learn grammar and pick up some vocabulary along the way.) I imagine it’ll be difficult to target what others should or should not know.
That said, it sounds like what you’ll ultimately have (if you allow for user contributions) will be not unlike our book club vocabulary lists, where people may go to the list to look up a word they won’t know, find it’s not on the list, look it up elsewhere, and then (hopefully!) add it to the list for others to see. I’d say it works well enough for the book clubs.
To reiterate what I said before, I’m absolutely looking forward to your project’s potential and what the result will ultimately be.