Just for the record, I can't afford to be a playtester and help with that process but I'd love to. However, I'm just an end-user, and there's something I'm seeing a lot of that I'd like to get out of.
Many groups charting vocals are trying to fit all the vocals in, which is extremely hard to sing because it's unnatural. For example, the chorus on "The Final Episode (Let's Change the Channel)" has many switches between clean and unclean vocals where it's obvious that they're separate vocal tracks. There's no room to breathe or switch vocal styles, making it hard to nail that part. The same thing happens a couple of times in "Battle Royale".
While I understand that some groups may find it important to chart all of the vocals in a song, I think it's better to think of it as "What parts would the singer sing live and what would be handled by a back-up singer?" It's more important for a song to work well and feel natural than to have all of the vocals charted. Just some food for thought.