These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
YMMV: Samurai 7
Complete Monster: Ukyo is a nasty piece of work. He was born in a village where he was oppressed by the Nobuseri, and at some point, he was adopted into a noble family, where he was pampered into being a ridiculously selfish and arrogant sociopath who places absolutely no value on human life. When he becomes Emperor (long story), he takes control of the bandits like his predecessor did and has them attack the villages. Not content to stop there, he even told the Nobuseri's leader to take the food that the peasants stored away so that they could, you know, not starve to death — even the bandit leader (who knew about these stores) felt that he was going overboard. Then Ukyo personally brings an army to Kanna Village so that he can wipe it out. He has several reasons for this, but the biggest one is that he wanted Kirara to be part of his Paid Harem, and her reply was essentially, “go screw yourself.” He places so little value on human life that when he sees the corpses of his Paid Harem, his only response is to say, “Oh dear, they won't be easy to replace.”
Growing the Beard: The first two-thirds of the movie follows the plotline of the original Seven Samurai as close as it can, which works as well as you would expect when you adapt a 207-minute movie into sixteen half-hour episodes. The last third is an original storyline, allowing the series to finally stretch its wings and kick things into Serial Escalation territory.
In Name Only: The original source (the movie Seven Samurai by Akira Kurosawa) did not have any of the following: mecha, the village priestess or her Annoying Younger Sister, Ukyo or his father or the whole plot involving Ukyo's lust for the village priestess, super-human samurai who can jump from spaceship to spaceship in hard space without any protection and slice mecha in half with only their katanas, robotic samurai (which some people believe kills Kikuchiyo's characterization and motives completely), one of the seven actually working for the bandit-mecha-warlord... etc, etc.
The Scrappy: Katsushiro is hated by a good part of the fans, for his whininess and for accidentally killing Kyuzo.
Woolseyism: The English Dub takes several liberties with the translation. Some of it may be justified in that there are a lot of throw away lines that either reference Japanese culture or are puns that only work in Japanese. Changing these is more pragmatic than anything.