I love it when the visuals or audio style of the VN complement it or define it's own unique identity (doesn't have to be a unique style). From my experience as well, VN's that utilize the audio and visual aspects draw me in a lot quicker than normal novels. This is even if the base story or depiction is comparable.
As I found out from Subahibi, Dempa's not really my thing, but maybe I'll come back to this VN. Even though I kinda know what is happening in the VN, somehow getting a hint as how to interpret the (what would normally be) madness makes the VN a more agreeable read. I quite like the observations you made: they're clear and relevant, interesting, and not presuming.