Ranking characters:
9) Mira. A weak, generic antagonist who is responsible for way too much despite having little prominence or depth. Her design sucks. Her ending sucks. Character just sucks.
8) Eric. Had significant potential, but he literally does not (and arguably cannot) develop at all. Mostly used as a plot device in the latter parts of the game (shotgun-kun).
7) Diana. Diana is a very strong and compelling character; I just don't like her that much.
6) Phi. Nowhere near as amazing as she was in VLR. She's just cool I guess.
5) Sean. Arguably the most compelling character in the entire game. Pretty much keeps Q team afloat, and is responsible for some of the game's best moments. (ie: Happy End)
4) Akane. They mixed elements of her character from 999/VLR and the result was... strange. When she's not being a massive hypocrite, she goes on psychotic rampages (chainsaw-chan) and is generally an awkward and unintentionally funny character. Easily the most entertain character by far.
3) Sigma. Really strong character (have you seen those muscles) and pretty much has all of the best moments in the story. His only flaw is that he doesn't really act like his 67 year old self from VLR.
2) Carlos. For murrica. The protagonist™. He's not particular deep, but his personality and backstory make it easy to root for him. He's just an awesome dude surrounded by profoundly shitty people making the best of his current situation.
Best theme song.
1) Junpei. He's super duper good now. Junpei graduated from your dime a dozen VN protag (strong sense of justice was an actual character trait used to describe him. yuck) into an actual character. Sure he's acerbic and insufferable, but who wouldn't given his situation. I just think his reaction to events in the game are super natural, and pretty much something a regular person would that. So I guess in that sense, he's also a really good audience surrogate to? There's also this: