I think overall they did skimp on the battle scenes (throughout the series but surprisingly in the final episode) to stay within budget.
I definitely would have liked to see more closure with Ishido-
IMHO I wonder how Japanese, Chinese, and Korean people think of this show. They watch huge numbers of similar type of dramas, this one was written and produced for a western audience. I know from the Japanese POV that they think that samurai stereotypes (fanatic loyalty, honor, Zen, suicide etc.) are largely exaggerated even in though own media.
I like the inclusion of so many Zen Death Poems. It is consistent with a book on Zen Death poetry that I read a while back. Most of these poems were written at the end of life and not before suicide or execution though. A lot of them are brilliant, however the most common 'theme' among Zen Death Poems is how the person basically says that 'death is nothing', merely the next phase after life.
There are so many seppeku in the show/story that the later ones has less impact for me. I wonder how a Japanese person would react to this, as this story is written by a Western man.
With Mariko she should not be thought of through the 'Western' conception of morality even though she likes christianity