In terms of character development I see it more in terms of how smooth the world building and establishing the lives of the characters in that world.
I have seen some VNs that will try to establish a deep back story for a character, where the more interesting and entertaining aspects of the story takes a back seat, in those cases, people can find themselves rapidly skipping through the text without really reading it. The video game equivalent of that would be taking a game like skyrim, and making the first part of the game reading through all of the lore books found scattered in the game world before you get to start your first quest. That method will make many people in that game a lot more well rounded, but it would also mean that 90% of users will never make it to the first quest before dropping the game.
There are also some games where the main campaign seemingly has no story because all of the world building was done in random books and notes that are easy to overlook.
Usually the best overall are the ones that manage to strike a balance of developing the characters while also moving the main story forward. For me, since I see elements of a balance, the indicators are pointing in the direction of a well rounded character, even if that rounding is not yet complete. Given the length of the first release, if the character ended up well rounded already, then the first build would have been more of a fictional biography textbook and less of a VN.