After comparing Naotsugu's lines between the anime and the light novel, Akatsuki's flying knee gag makes more sense. In the light novel, Naotsugu gets to say some of his more perverted (and sometimes, somewhat sexist) remarks. Those lines are cut out of the anime by having Akatsuki knee him in the face, with him complaining that she should let him say something perverted.
Re-Gun's meeting with Shiroe seems very coincidental (in that Shiroe is the protagonist and this person just so happens to have been looking for him). However, the lore for the Half-Alv race is that they have higher magic stats and storyline bonuses in dungeons and certain quests. Re-Gun, whose title "Sage of Mirror Lake" is well-known in game lore, is essentially a storyline bonus for Shiroe. Furthermore, since Shiroe is a Half-Alv, he has the potential to perhaps use the Alv's magic, which is probably what Re-Gun was interested in.
The light novel created a parallel between Rayneshia and her father, Feynail. He married into the Corwen family and was often criticized by others as being too weak for such a powerful family. Rayneshia, despite her affluent background, is not expected to take part in politics and knows that she is just there to look pretty. It is implied that through Feynail's actions, he gained the favor of Duke Serjiad and married into the family. Similarly, Rayneshia decides that taking no action in a time of dire conflict would disgrace the Corwen family, and unveils her plan to personally plead with the Adventurers since the Lander's only other hope, the Knights of Izumo, was missing. Through her actions, she gains the favor and trust of her grandfather, Duke Serjiad, just like her father had.
For volume 7, Mamare released some extra info and pictures on Silver Sword's raid party whom Shiroe and Naotsugu go with. Each member gets a quote in their profile, along with their name, class, subclass, and most commonly used skill. Although the quote seems, at first, to just be a line indicative of their personality or playing style. However, after reading the web novel, the character's responses are much more enlightening and, in some cases, heartwarming.
William Massachusetts says "So what. I don't give a shit," which was his reaction to getting wiped and the despair he felt. Right after him, in his group, is a member who says "I agree. Gentlemen, we shall be successful next time," which shows his faith in William and William's determination. Another member says, "Good, turn your hatred into passion," a response to William's confession about his hatred towards the Debauchery Tea Party for disbanding before he could join them after he had aspired to be among them for so long.
Isuzu's story of how she began playing Elder Tale has some more terrifying implications. She was given a one-week pass to play the game for free by her older brother, and so she decided to play it for fun and had no intention of continuing after the pass ran out. If some of the other beginner players are the same way, they just became trapped within a game that they had no intention of getting immersed in, with no idea whether they'll ever meet their friends or family (who probably take higher priority than Elder Tale) again.
An out-of-scene Whatever Happened To The Mouse feeling comes over viewers when adventurers seemingly don't discuss much about the friends and families left behind in the original reality. Krusty has memories of a pet cat and a sister but doesn't seem overly concerned about their welfare. What about the adventurers who are parents of young children? With younger players such as Isuzu and Minori: Are there worried and traumatized parents who lament their loss? A more dramatic scenario might be that the World Fraction, the magic that reversed reality for the adventurers also caused The original world to cease existence and leave only shadowy memories of the old world. Else, the adventurers should have a great deal of mental trauma about their situation.