Wow, what an emotional, unimaginable, senseless crime. Perpetrated by this murderer hiding in the shadows. We know he drove past the 1122 King St. on 23 occasions from August until the murders. This wasn't just a random act on random people, it was a well thought out, timed and planned event. Thank goodness he wasn't smart enough to pull it off perfectly.
I believe he specifically targeted these young women in that house, who represented everything he hated about women in general and his own pathetic life. Ethan just happened to be in the wrong place at the wrong time. He followed one, two or maybe all of them on social media at some point where they all had a large, open online presence. Maybe even before he actually arrived at WSU.
I think his main target was Kaylee (destroying her very identity - facial features left almost unrecognizable

). He committed the act that night because he had to. Kaylee was back in town for essentially the last long weekend before graduation, which he would have known by following her SM accounts.
I also think it's likely that he actually was behind the Papa Rodgers account, no proof, JMO. Even if LE couldn't/didn't definitively link him to it, he was well versed enough in computer technology to erase the digital trail. We know through the documents released that he used software to do that.
He made the Plea deal because he knew the State had a rock solid winning case. He was beaten after all the Motions and rulings against the Defense in the last hearings. He wasn't sorry or remorseful, he didn't care about his family, it was simply a matter of self preservation.
I hope prison serves him exactly the Karma he deserves.
JMO