1. You're confusing the Main Character with the Player, they are not the same thing. The Main Characters are advertised on this page. They are Lin, Kali, Ashley, Maria, Android, Felicity, Emma, and Autumn, with another on the way.
However the player controls a character who is not the center of the story, rather the player character plays a supportive role and is narrative vehicle to push the story forward. The player character is not the hero, the women are.
2. You can change the radio in the pause menu, I recommend Chill City but there are multiple radio stations for you to choose from. This has been in the game for about a year now I think.
I am planning on a music update eventually! I'll be going back and adding music to most events and giving themes to stuff like dates and such.