I have been a former player of VNs for some time now and i have spotten a few things that most VN don´t have such a protagonist with voice, among other things.
I would to know everyone suggestions about this topic.
Totally generic response here, but the most important thing is excitement. If you refuse to close out a VN because "NEED MOAR" it's done its job well. This can apply in any kind of flavor, be it Action, Suspense, H-content... etc. If it gets the adrenaline pumping it's good.
More specific response... my two favorite VN are Fate/Stay Night for NEEDS MOAR ACTION and Wanko to Kurasou for NEED MORE CHARACTER INTERACTION + CHARACTER INTERPLAY + H.
What a VN needs:
Loads of Action like from a movie( fighting)
10 star H-scene
Awesome story with good background
Good Art
Interactive system? like Sengoku Rance or Utawarerumono
Awesome Climax
THe girl... (you can`t just go spend nearly whole day just to get the girl you don`t like (the art and the personality tsundere, yandaere, dandere, kundere, etc)
Story..... (One of the things that motivate you to go on)
H scene ( the bonus that u wait as a reward for getting the girl)