I wouldn't say the plot is that different until the last parts of it, it's mostly the same but lacking the South Galaxy sub plot, which is a significant portion of the manga but its just skipped in the Anime, the big changes don't start until Rai's Wedding
Unfortunately the anime only has horrible old Hong Kong subs for English, the subs are so bad that not only characters names but the name of the show itself in the intro are translated differently from episode to episode, this Fan translation is the first time this franchise can actually be...
I know you said that since there's no chapter cuts on the volume's you're using you're just deciding one a set number of pages to mark the start and stop of chapters but this chapter in particular feels like it should end just one page earlier. The chapter before it though feels right to end...
iirc in the Anime after Rai and Rakou kill each other in a final one on one duel. Toramaru became the Galactic Emperor that unified the galaxy with the support of Rai's military
Finally the greatest rivalry in this series begins Rai vs Rakou the biggest difference between the anime and the original is that here, we get an entire side story tracking Rakou's development as the Manga goes on, Rakou becomes like the Vergil to Rai's Dante
"Galaxy Warring States Chronicles Rai" Another way to translate that is 'Galactic Sengoku Chronicle of Rai' or 'Galactic Sengoku Rai's Chronicle' because Sengoku is one of those words that when just Latinized instead of translated evokes a meaning on it's own, since the title is supposed to make...
Ah this is where the mother of the protagonist from the Sequel manga debuts, I'm going to try to figure out at what point in the series she got knocked up because I don't think the sequel manga says it and I want to know if its actually possible within the original manga's timeline
Well you can't just let a Pedophile live, he had to be dealt with somehow, Introducing his character at all, especially this late was a massive mistake but once it's done it has to be resolved one way or another