I'm only interested in keeping this story enjoyable, not the whole fantasy genre.
You know, to exaggerate a little, what good was Ikta's brilliant first plot in the show, to get the group back to the empire using the scheme with the hot air balloon, if Yatori could have simply slaughtered every enemy soldier at the border post instead, allowing them to pass just as easily and even keep their gear? With Ikta's plan there was still a high chance of something going wrong as it really relied on the opponent making a hasty decision under stress, but with Yatori simply killing everybody, nothing could have gone wrong since there wouldn't have been an enemy left standing.
See what I mean?