Even if I wasn't already enamored with this franchise from the novels, episode 7 would have hooked me deeply. That's because it shows the story starting to stray into territory not normally covered by isekai stories involving game-like settings: the bigger reasons behind why the world is structured like a game.
The first indicator of that comes early in the episode, with Oka's surprising pronouncement to Schlain and Katia that accumulating too many skills is dangerous. When the later incident with Hugo comes up, it seems at first as if his behavior is what she was referring to: that high skill levels breed runaway arrogance. (Indeed, we can see a bit of this in Kumoko.) However, Natsume was arrogant back in Japan, and his contempt for Schlain comes naturally from him thinking that Schlain is stealing his spotlight. Hence skills do not seem to have much to do with why he ultimately tries to kill Schlain. So what is Oka referring to, then, and why is she being secretive about both it and the location of the three reincarnations whom she hasn't been able to reach yet? (And is one of those Hiiro Wakaba?) For that matter, how does she even know about skills being dangerous? The only thing that separates her from the others in this world is that she's an elf, so presumably knowing this has something to do with them.
Hugo's attack on Schlain during the camping trip was not a surprise, but that did not damper much the intensity of it. Ironically, this shows the danger of not pumping skills and levels, as it left Schlain at a disadvantage that he shouldn't have had, and clearly Oka only stopped him because hers were stronger still. (Notably, Schlain only uses Appraisal on Hugo, not Oka as well.) Then there's also the matter of her exercising “ruler” privileges to reset Hugo, which presumably means that she has a title similar to Kumoko's “Ruler of Pride” and “Ruler of Perseverance”, as well as a better understanding of how to use it. Has she been pushing her skills like Kumoko has? If so, why isn't she following her own caution?
The final scene shows that the story is far from done with Hugo, however. As he is raging about getting revenge, a new figure shown very briefly in the opener appears. We know from advertising copy that she is Sophia Karen, and she claims to be a fellow reincarnation. She has vaguely pointed ears (but not in an elf fashion) and reddish eyes, so she is not human. Given the way she suddenly appears, the natural guess might be vampire, though if that is the case then this world does not follow the “no reflection” rule for vampires. She did narrow her eyes at Hugo's demon reference, though, so whatever she is, she probably has some connection to them. (That would also presumably make her one of the three that Okaa has not been able to contact so far.) But what kind of assistance is she planning to offer?
On the spider front, Kumoko mostly seems to be just messing around with skills, with her lighter side tied up in connecting the Evil Eye possibilities to classic chunibyo behavior. However, some curious developments come out of even that. The static bursts as her Appraisal and Detection max out are the next hints of a bigger picture vaguely suggested by earlier “MA field” references, and the first mention of “Administrator D” comes up. This is the first real indicator of guiding forces behind the game-like structure – in particular, a being specifically influencing it. Though Kumoko is benefiting from having her wish granted, why she is freaked out by this is totally understandable. Someone – possibly this D – does seem to be actively watching her, so is the shot of Kumoko on a computer monitor simply imagination or literal? And why did that being grant the request so quickly? That Kumoko's behavior so far is just that entertaining seems like a reasonable supposition. Since this is coming up in the same episode that Okaa makes her statement, a connection between the two factors can also be inferred. The anime adaptation is structuring things quite deliberately, after all.
And speaking of that, the reordering that I suspected last episode did, indeed, happen. In the novel, the earth wyrm attack from episode 3 happened while Schlain and crew were returning from this episode's scene, but the order works better this way since the earth wyrm incident gave Hugo a more strongly-justified motive here. The scene where Kumoko gets Wisdom happens at about the same time in the book, and some of the end scene is an adaptation of an interlude right after, so the two sides are, for the first time, almost exactly in the same place in the source material. However, Sophia's appearance at this point is anime-original. That something like that had to have happened was at least vaguely implied by later events, so it is a logical addition.
If you were wondering about bigger plotlines showing up, they are starting to firmly materialize on all sides now. Things will only get hairier from here.