It may have also been a function of needing to nerf the lighter autofire weapons, primarily the HBR and the LRB. Because of how Autofire was tuned when those changes were made, they were exceedingly vicious weapons, and now they play reasonably well. Since the HBR "should" do more damage than a BR, they had to drop those damage ratings down, too, for internal consistency, or something.
TBH, our group saw very little diffrence in the feel of play before and after that change.
On the other hand, melee weapons, especially the vibro weapons, got nerfed 6 ways from sunday in one of the early patches. I don't really remember the rationale behind it, though. The vibro weapons got buffed up a little bit by increasing the pierce value on the knife and reducing the crit activation costs. If you'll excuse the pun, the point of the melee weapons (get it? point? Knife? pointy end goes in the other maBACK OFF I'M TRYING!!) is not so much to inflict damage, but to inflict crits. To be honest, though, the melee issue hasn't come up much in our games and my 'crit theory' above is largely conjecture. We just don't really have melee orientated characters in our group.