This is the best Light Novel series that no one read. I mean, seriously, look at how few ratings the books have. This really is a shame- It seems like the Japanese strategy of (often) half-heartedly directing a season or two of anime adaptions of LNs really pays off: Eromanga-sensei has more review than this series, it really is not about quality, it's about popularity.
The second half of the second volume was as strong as the first one. In total, I think the second volume is WAY superior to the first. The world building, which was bombastic for LN standards in the first volume, is somewhat toned down, but this makes sense when looking at all the character development going on in this volume. Even the supporting crew of Sayama's security company / family had character development, for crying out loud. Kashima and his family are honestly the ones carrying the novel for me; not that the rest of the cast was weak - ALL main members, newly introduced Gear inhabitants and side characters get their slice of literal cake of character development - but this was surprisingly the first Dad-pov I've read in a light novel or Japanese novel at all, and the concern for and concept of family influencing Kashima's actions were just great to read about, Kashima, in general, might be my favourite character of the series so far.
So, if you stumble over this review and like what you've just read, please start with the first volume, part one, and I will guarantee that the quality of the writing will make you stay at least until this novel - up to now the beast of an author that Kawakami seems to be has shown no signs of slowing down!