The amazing music of the game makes sense from a meta-standpoint. The Musicians and µ gain power by having everyone listen to their songs, hence they are the themes for the various dungeons — making the songs enjoyable to listen to on repeat leads to it not bothering the player as much to hear them all the time. Even if the player detests a certain dungeon because of its gimmick, characters, or even just the design, the music is enough to not make it too annoying to listen to.
Stork's theme song Love Scope sounds like a typical yandere-esque love song about going after their target of affection, even if they are being rejected. Pretty 'girly' lyrics, as the game has Stork's song described that way. Then it turns out that Stork is a The Peeping Tom, making the song decidely more creepy. Treated this way in-universe, too, when the Go Home Club realizes the actual meaning behind the lyrics.
Looking at the lyrics for Ike-P's theme Angel's Song sound pretty positive. Unlike most of the other Musicians' songs, it doesn't revolve around feeling crushed by their view of the world or boasting about their own amazement. It talks about going beyond what fate or life may have in store for you through determination and guts. Considering his personal trauma revolves on disliking his average appearance, this seems pretty understandable. Compared to some of the other Musicians — like Kuchinashi being severely traumatized by a fire that killed her family, Wicked's abusive past having left her with an incredibly twisted way of thinking, and Thorn still torn over her friend's suicide — his trauma isn't as emotionally scarring.
Lucid not having any battle voice clips makes sense. If they were to speak, then the Go Home Club members would immediately recognize them as their club president.
During the Musician route, there is the chance that Kotaro ends up dying in Mobius, which means they die in reality, too. Now think about his homelife and what his cousin said: because Kotaro is suffering from the Astral Syndrome, he has been losing weight and the family has been scorned by neighbors, to the point that his aunt can't even go outside anymore. Now imagine what will happen if Kotaro dies! They could be so paranoid about what people will think now that their adopted child has died, they might try to hide this fact from the world — perhaps burying Kotaro's corpse somewhere?