The plot premises were relatively original, but somehow the stories just felt flat. Probably because the pacing was off - As is often the case with oneshots, the pace was too fast, and there was no room for character development.
As I was reading the first story, I was thinking of rating this manga only 1 star, but after reading all of the stories, I'll rate it 3 stars.
There's another manga, 'Kinpeibei Kinden Honoo no Kuchizuke', which is a sequel of the last - and best - story in this manga, so I do want to read it. I'm trusting that it'll be better, as it's longer.
Mugen no Roukaku