For what it's worth, as someone not too impressed with Jarvis initially, I actually thought he did a good job overall. But there were a lot of times when he went full blown Bo-Jo. Sort of buffoonish. Face like a smacked arse. And I don't remember thinking of him like that in the book. But i don't think it took away from the whole thing in the end.
I thought I remembered a huge end battle in the book. Maybe I've completely mis-remembered. Though I completely forgot about the main talking point in the penultimate episode so who knows. Maybe I didn't even like the book really. God knows.
The show showed more of the battle than the book did. At least the show depicts what Toranaga predicting what the battlefield will be, with the armies on scene. The main story ends before even that, with an epilogue stating that Toranaga won at Sekigahara, with the battle lasting 6 hours before Ishido's armies broke and 40k heads were taken (seriously, the above is only abridged by a few words). The main part of the post-Mariko story involves looking at Mariko's impact, before shifting to Toranaga's POV which is basically his monologue with Yabushige. Episode 10 is wholly in the style of the book's ending, suitably condensed into one episode.
What this show misses in comparison with the 80s version is much of the Christian shenanigans, and Anjin's relationships with other characters. Given the low opinion some have here of Jarvis, maybe this was for the better. What this show plays up and focuses on is the Japanese politics. Oh, and it's historically the best version of the three, being the only version critically acclaimed by the Japanese themselves.
