Well, your opinion is to be respected of course, but the Japanese were, are and always will be, a skilled people for whatever has to do with war. During the Sengoku period this trend was sharpened to new heights.
I understand the point about being confined to styles, however i would equally welcome a TW game during the Romance of the three kingdoms in China. I know very little about Korea - other than the fact that it was under the heavy shadow of China in the medieval era and later during the modern times under the heavy shadow of Japan. Its national martial art tae kwon do - is nearly a renaming of Okinawan karate that Korean immigrants brought from Japan pre WW2, but could not practice with a Japanese name due to the national issues against Japan in Korea - not exactly a great martial tradition when you compare it to Japan's.
As far as weapons are concerned, japanese swords - katanas - are the highest quality hand-to-hand weapons ever produced - metallographic analysis in the highest quality european swords (from Toledo) showed about 200,000 layers of iron/carbon in the steel alloy. The equivalent number for a katana is 1,500,000 - making it a killing tool that hasn't been repeated. Other Japanese blades for yaris (spears) and naginatas (halberds) were of comparable quality.
For me only a single "style" is not a problem especially now that i know a lot about this particular one - although again your assumption is misleading - Sengoku Daimyos were particularly imaginative when tactics and strategy were concerned and were keen inovators in many instances. It was also not a problem in the past when i knew nothing about japan, its history and its warring tradition.
Perhaps your opinion is based on a misunderstanding or lack of understanding - in that case S2 provides a great opportunity to sort this misunderstanding for you - you never know.
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