For reading #1:
According to Price, the unifying theme in all of Linklater’s films is the idea of idleness, particularly the idleness of the young and poor. Rather than glorifying or condemning idleness, Linklater simply explores the effect that it has on people. He is also very interested in time as a concept, and how it can be manipulated through the medium of filmmaking.
For reading #2:
I think that "style is the artist's means of defining the relationship of the spectator to the film" is another way of saying that style encompasses every method a director uses to influence the viewer’s experience as they watch. Everything that a filmmaker does to put their own unique spin on things, or to make separate films feel as if they’ve all come from the same mind or source, is “style”.
As for Linklater’s approach to making Before Sunrise, I think that incorporating elements like improvisation and collaborative scriptwriting do give the film a sense of realism. For instance, allowing the actors to draw from their own personal histories is an interesting way to give the characters a believable back-story. I think that, to a certain degree, drawing on past experience is something that all writers and actors do to ensure a sense of realism.
Film definitely has the most unique relationship to time compared to other mediums. You can look at a painting for as little or as long as you want, or you can read a book all in one sitting or spread it out over a period of months, but a film takes a set amount of time to experience the thing in its entirety. And of course, time has to pass within the storyline of the film, which opens up endless possibilities for how time is experienced by the viewer; the story could take place in real-time, or it could be non-linear, or it could encompass the entire life of a character from beginning to end.