It doesn't make much sense that a G3 will OHK within 20m but an FN MAG or M110 SASS firing the same cartridge will do at most 87 HP of damage to the same target. The 20m rule also feels like an inconsistently applied half-measure that does not fully address the issue.
Giving all full-calibre weapon platforms a guaranteed OHK capability with a torso shot within 100m (more extreme option could be 300m) would give these weapons a seriously meaningful advantage over their more ergonomic and easier to use intermediate cartridge competitors. It would make MGs, DMRs and Battle Rifles significantly more viable and tangibly threatening knowing that it would take only one shot to put a player down. It would also buff across the board factions who rely heavily on this calibre for their weapon platforms.
This would provide a much more prominent pay off for dealing with 7.62-based platform's objectively inferior handling and It would solidify and emphasise their medium-long range superiority over intermediate cartridges.
The damage values for 7.62x51/54R seems somewhat arbitrary and could do with some refinement. This might prove an unpopular idea but It's more to see what people think of the current 7.62x51/54R damage value balance with an extreme suggestion to garner opinion.