I am pretty sure that the TOS folks werent thinking in terms of arcs, but these episodes all seem like part of a continuous narrative involving the Klingons, the Federation, and the balance of power, especially in pacifistic and/or pre-warp civilizations. A direction that would have been interesting to follow...
I like S3 a lot (unlike many), but they do seem to have largely dropped this potential arc.
I like S3 a lot (unlike many), but they do seem to have largely dropped this potential arc.