Brain Salisbury posted his interview with Keanu Reeves for Movie Pilot. This interview is fully focused on the film. Among other things, Keanu talks about developing the John Wick character saying:
It was a big part of the preproduction and creative process with the directors and the wardrobe designer. What is he going to wear? What does that suit look like? And then it turned into the hair, the beard; length of hair, beard or no beard? How does this suit fit? What does it all mean, this armor, this character, this transformation? It was fun to put that together. The filmmakers had a real definite feeling they wanted to convey. When they saw the silhouette of John, it was there. When you put it on, it felt right. Also, when he looks at his own reflection, he has a reticence. There’s an ambivalence to it, but he’s also gonna do it. It’s there.
You can read the entire interview here.