I was thinking it could make a good run to do all confidant max rank and social stats full while getting true ending. Thought?

For All Confidants, @NanashiExile already does/has done those. Their old PB is even on the boards.

Full Social Stat though just seems random. There comes a point where there has to be a common ground on what a "Max" run is, otherwise you would just keep creating further new categories that max something else that the previous didn't.

Edit: Personally, I think that True Ending is already a good "Max" definition. The thing with all confidants is that from a routing perspective it would be fun, and would require you to work out the optimal way to do a lot of the game's systems. However, from a run perspective it would essentially be almost identical to Hard, True Ending when it comes down to it, and largely just result in more cutscenes. There's definitely people who like All Confidants, @NanashiExile is proof of that, but would the run be that different it warrants being its own thing? I don't think so. In the long run you'd see Hard, True Ending and All Confidants, and All Confidants would be mostly the same gameplay wise with just several extra hours of cutscenes/activities on top of it.