@Bobbias : this is one if not the only feature I really want to see implemented in osu! right now.
If it were to be a thing I'd be glad to help out with modding and such, and I am sure many more would be willing to contribute to the ranking process. At least, I know I would and I'd abuse it all day long in the editor. Figuring out what was the mapper thinking when he made a map can be really tricky at times and it would help with common "unrankability issues" (OVERMAPPING/GHOST NOTES ANYONE ?).
Now that I think about it, since we have 9K rankable now, there is no no doubt we will see really hard maps getting into the ranking process in the future, and I think that modding/pattern recognition might get even more messier with that amount of columns and the possible insane amount of notes on screen. Though this is unlikely to happen soon, and it's a minor point considering every pros to this feature that have been mentionned until now, it's still worth considering. Actually, I don't even see it having any cons at all.
Also wow Harby, dem stars lmao.