I am not sure if any of you are aware of this so I thought I should make a post about it. Tap (currently translating the latest SAO LN) made a twitter dedicated to post translations of Kawahara Reki’s live commentaries for each SAOII episodes.
Every week, Kawahara-sensei would watch the latest episode and do a live commentaries on his twitter. He explains a lot of scenes shown in the anime. Most of them are information already mentioned in the light novels. However, sometimes there are extra information as well. He also offers his own opinion on some scenes and it’s really interesting to read. So if you have some spare time, I would highly recommend you to read his episode commentaries found on the twitter link above.
To make reading easier, Tap also creates a pastebin version of the commentaries every week. You can find them here. He updates the post weekly so just keep an eye on it if you are interested!