You appear to have missed my point: adding a bunch of weapons to the 5E list is meaningless without a more granular, detailed system to differentiate those weapons. AD&D had a significantly more detailed approach to weapons (not that anyone ever actually used it) that made a list of a dozen different polearms worth having. 5E's system as it is differentiates weapons by damage, handedness, simple reach and a handful of other traits -- none of which are going to make it worth listing polearms separately by era or nation of origin.