I won't be able to write for a hot minute but ahhhh I cannot stop thinking of NEO!777 and also I can't sleep so here's an unorganized dump of shit. I'll write proper headcanon posts,,, ehhhh eventually??
777 was brought back after the long game; he was illegally erased by another Reaper and Joshua is attached to his emotional support rockstar. (This is canon in the anime so it will be canon on my blog >:/)
777 was physically recovering from his injuries for around a year before he was able to create music again. He had severely broken ribs, as he was caught between the RG and UG (he attempted to phase to the RG to escape but didn't fully make it.) Due to being injured in both planes, he couldn't heal as fast as Reapers normally due when injured. He's a workaholic and it's SO HARD for him to sit down and heal which made it longer smh. He also had decreased lung function and had to retrain himself to accommodate it.
If you scan someone at Tower Records, you can find out that Def Märch is working on a new album. (I highly doubt BJ and Tenho would continue to make music without 777: he was the band's soul.) There are also posters that say ILL DEAD around Shibuya, but unlike the first game where they say "New Album: in stores now," in NEO it's changed to "1st Album: In stores now," which imo, implies that that's THEIR album. (Though in my canon, they have an extensive library of albums and music since they've been making music together as Def Märch since the 90s.)
The commentator reaper is 777. I will not be told otherwise.
For the above point, Shiba was likely looking for someone with a passionate and "fiery" voice to "heat up the excitement." Of course 777 was pointed out and appointed to the commentator position. He rather likes it too, he gets to use his own skills in order to earn points and he gets what's basically free entertainment. (Though sometimes it shows that he's not the most experienced with commentating)
777 prefers the Shinjuku's version of the Game, if you were to ask him. Team work is something incredibly important to him-- when he played his game he managed to forge a three way pact because of his strong his imagination was. It's probably a relief for him to see these groups of Players teaming up with another.
There's things he doesn't like about the reformed game however. Primarily, the lack of entry fees and lack of push to better ones self. The development of a person during the game is a concept that 777 understands and even agrees is necessary. He went through it personally.
Due to the lack of Reapers after the Long Game, 777 begrudgingly took position as an Officer, provided he could still do Harrier work and interact with players-- essentially only an Officer in name.
He may not get along with Uzuki as Game Master, but he genuinely trusts her judgement on how to run the Game. It's something she's passionate about, and he respects that.