"Yes," is the first non-Japanese word Fuji-sama speaks in the entire series.

"Why tell a dead man the future...." This quote is critical because in the first episode, Yabushige tells Omi the same thing. The point was that from the very beginning, Toranaga was working on his grand plan, but adjusting with the times. "Let your hands be the last to hold her...." same idea, this was Mariko speaking to Fuji in the first episode. The closing of the story arc, same with the idea of letting go. Both Fuji and Anjin let go of the past, and moved forward with their lives. Anjin was a changed man. He never would return to England. It was all a "Dream within a dream...." When he attempted to commit seppuku, his old self had died. He was reborn. One story note about the ashes scene, the screenwriters picked that specific place for a good reason. If you listen to the show's podcast, they explain. That beautiful coastal area in Northern Vancouver/British Columbia was also at the favorite place/vacation home of the author James Clavell. When he passed away, his family spread his ashes in the waters in much the same way. The closing of that story arc. Magnificent storytelling.

The thing is that toranaga isn't an ocean's 11 type where everything goes according to a plan. Toranaga is pragmatic strategist and is significantly more realistic. Yabushigi asks toranaga how it feels to bend the wind to his will but toranaga responds that he doesn't control the wind, he studies it. Toranaga has a basic plan that pushes pieces into place but it's impossible to control fate. Toranaga observes what is happening and makes decisions accordingly. That being said, people are often predictable and can be unknowingly steered to a specific outcome like a hawk. While a danny ocean will have the whole game from the dealer to the cards set up from the beginning toranaga makes the best moves with the hand he was dealt and his understanding of the behaviors of everyone at the table. Ocean is essentially performing a magic trick, where as toranaga is playing a game of chess. To answer what religion the Japanese were in this era, they were mostly a Japanese specific version of Buddhism which combined Buddhism with existing Japanese spiritual beliefs. Crimson sky is actually an example of toranaga's trickery in action. He first convinces his allies and by extension his enemies and the audience that crimson sky is an all out assault of Osaka castle. He then convinces everyone that he has givin up and is truly surrendering. This is why literally no one knows that crimson sky is still on or the true nature of it when it happens. Not showing the battle of sekigahara is a very interesting creative choice. Where as most Hollywood movies would often choose to muddle the meaning of the plot and themes with a gratuitous action scene, shogun decided it was unnecessary. The battle's outcome has already been decided because of what toranaga did and the revelation of toranaga's inner heart would have been buried in the action.

The scene with "old" John was a dream he had immediately after the blast when he was knocked out.

The scene where Blackthorne is very old was just a dream ("A Dream of a Dream"). That's why he was holding the same cross that he threw into the sea. The real life person he was based on, William Adams, never returned to England. He married, raised children and died in Japan.

The concept of Noh is that life is like a temporary dream. It seems to have been a concept shared by the Japanese people of that time. It seems to me that the Samurai thought about “dying beautifully” because life is short. The reason why cherry blossoms are loved by Japanese people is because they feel the fleeting nature of life in cherry blossoms, which fall apart in a short period of time. Toda Mariko's line, “Flowers are flowers because they fall,” has the same meaning.

Since the series ended following the book, which was loosely based on the end of the Sengoku period. Imagine a following season keeping with a history inspired story with Toronaga becomes the main antagonist. Where the Tokugawa shogunate buries Ishida alive, forces the death of the heir and Lady Chacha, crucifying and expelling christians, and enforcing rule of Japan with his successors basically being dictators.

24:44 "Why tell a dead man the future". This was Yabushige's own words to Omi when he did not want to tell Toronaga about the arrival of the ship (ep. 1). He was basically telling Yabushige that he has been on him all this time and Omi was (also) his spy.

Probably Buddhism was the major religion of Japan back then. There have been Buddhist monks in the show and Toronaga's son's funeral appeared Buddhist - like.

the whole point of toranaga was win without kill his own people

If you want more action, I would wager that the new seasons which will come now with the monster success of this show will have more of the action you are looking for.

There will be a 2nd seasond. I, for one would like FX to leave this one alone as is. I don't want the show writers to make shallow plots just drag this into a multi season money making series As far as what historically happened, unlike in the series the Sekigahara battle did happen. Because of Hosokawa Garasha's (real life Mariko) death, many nobles switched factions and turned the tide of the battle. Ishida Matsunari (real life Ishido) lost and committed seppuku. Years later the heir with the support of his mother (Ochiba in the movie) launched a rebellion to take the Shogun title he believed to right fully his. He lost. He and his mother committed seppuku. As shogum Tokugawa (real life Toronaga) closed Japan from outsiders. He expelled the missionaries and persecuted the japanese Christians (like in ep. 10 ). He and his descendants ruled japan for about 250 years until the emperor took back power (with the help of nobles unsatisfied with how the clan was ineffective in stopping western countries pressuring Japan to open)