Hey, thanks again for playing!
Even though he's something that nearly every player will encounter, Sarcoph Augustus is technically an optional boss. So it's not unusual that you got the completion screen without beating him.
Yeah, the amount by which the focus mode concentrates your first is fairly subtle for balance reasons. For regular STGs usually the trick as far as positioning goes is to keep your player aligned with the enemies / bosses in order to deal optimal damage. Since Vacant Kingdom has 360 degree aim, that dynamic can't be the same. So instead, the risk-reward dynamic for positioning is based more on distance from the boss, and the amount by which your bullets arc outwards is critical for tuning that. Still there might be something I can do to make it more obvious that focusing concentrates your fire. Maybe longer bullets would emphasize the direction more? I'll play around with it.
I do have some plans on the front of NPCs not being forgotten. It's sort of alluded to in Prologue For A..., but I won't say for fear of over-promising. Good to hear that the moodiness music grew on you, I was worried that some people might think it clashed too much with the relative lightheartedness of the story. Noted on the highlight color contrast, little suggestions like that are very helpful!