I got the distinct feeling, after the last round of nerfing, that the collective Imm decision was to throw their hands up in the air and give these sets up as a bad job. Primarily due to the whining of a few people who wanted their lim1 shinies to be shinier in comparison to other people's shinies, over half of these sets have become, at best, levelling gear.
Given that I am really the only person who voiced an opinion that was against the original power of the sets, I take this a bit personally. I really love when people call opinions contrary to theirs whining because it shows how much they love to sniff their own asshole (and how little they respect others opinions).
Here is my experience with the warrior class set:
I built the 6 piece warrior class set after first round of re-balancing, prior to 2nd pass. It took about 3 days of persistence to acquire 6/6 (imo not very hard to obtain). After the 2nd pass of re-balancing i still wore the set, but eventually opted into what i felt was a more elite set which was straight damage. Had this 2nd round of re-balancing not taken place I would have gladly maintained the warrior set throughout my active duration of the wipe, while also having a multi stacked with the gear i eventually passed to my warrior in favor of.
It was only after the final round of re-balancing, in my opinion, the basic class set for the warrior was working as intended. It finally became worth opting into using individual item pieces.
If I started playing a warrior again this wipe from scratch (no multis with gear), I'd without a doubt try to assemble the class set, not as something to level with, but as reliable gear on a level 30 or legendary character. The fact is, most valued limited gear takes weeks or months to become available, and is far more desired and sought after than these class sets. I can't stress enough that there are some items you may not ever obtain in a single or several wipes unless/until the owner quits.
That being said, Jason, take a look around at your Myth peers. I guarantee 9/10 would love to have one of these 6 piece sets. Imo, insinuating that the class sets are a complete bust disrespects the time and effort people put into creating and implementing these sets (as well as everyone of your peers who would love to have one).
Finally, there are other sets being implemented as Hoss mentioned that I have not built, have not been revealed, and I imagine are far more difficult to acquire but also far more powerful. I have found one that would be a major pain to assemble but from seeing the stats of one piece can imagine the final results are phenomenal.