I think you misunderstood me. I was just noting that DRK borrowed a lot to flesh out its kit. There's nothing wrong with the design of the Job in FFXIV mechanically, you're still trading something (natural MP regen and outside MP regen) for power. I think the Job honestly could just use with some tweaking, especially revolving around the frequency of Dark Arts usage and the lack of damage and utility the Job currently offers when compared to its peers. Warrior also needs utility boosting, but that's a different topic all together.
You do realize that the enemies are supposed to stand in your salted earth, right?
Jabs aside, I doubt that the draining cost of Darkside was removed because of PvP. They likely wanted to do what they did to PvP since they released the Feast, it was just an inopportune moment to overhaul the system in such a way. In fact, PvP is likely the strongest aspect of the game right now, with each Job being rather well balanced and every Job having a specific niche in PvP environments.
As for your haughty idea of what PvP is, pruning the Jobs down to their bare essentials and removing gear as a contributing factor is probably for the best, since that sort of change allows SE not only greater control in regards to balance, but also makes it more like a fighting game, where each character has their specific attributes. If you think of FFXIV's PvP as more like Street Fighter or Tekken, it's easy to see how PvP is now almost entirely skill based.