When I originally added Death March to my light novel rankings, it was from the old point of view of just how good the light novels must be based on how good the anime was.
The new point of view of my books rankings is their value can only be based on the value added from reading the books themselves.
This meant that technically, having only watched the anime, Death March shouldn't be in my rankings anymore. However, I planned on reading Death March as soon as the anime ended so I just left it in there for now and figured it would become ranked legitimately with time.
I've now fixed that minor problem by reading volume six of the web novel (one week before the anime ends, I got too impatient.)
Now Death March is ranked for its value added like all the other series. In addition, now everything in all my halls of fame are things I've properly experienced myself again. Death March was the lone exception and now that's set right.
Now I just need to read all the subsequent books too, to prove how good the series truly is. But that will take a while, it's a long series. None of the other light novels I like are being translated so basically Death March is the only thing left to read in the world. Maybe once I finish this I can branch out and try some new series.
The book deals with events not covered by the anime because the light novels, upon which the anime is based, go a different direction from the web novels. That's why it's best to go with the web novels for maximum new content. The light novels aren't translated as far as the web novels anyway, so it's a no-brainer.
In book six, Satou tries out various ways to get stronger while solving a demon-zombie invasion of a poor barony. It's a relaxing and fun ride, not very deep or emotional. In stories of this size nothing much of importance ever happens in any individual book, you have to be prepared for the long haul. But one has to start somewhere, and this is the best place to start after finishing the anime, so I suggest everyone else start by reading book six from the web novels as well.