DNC is fine. They were already fine. The potency buffs make them a little bit less reliant on teammates, which is good, but the core of the class is always going to be "partner with the best teammates." Step one of being a good DNC is moving Closed Position around to who is most suited to using the buff you're about to throw out. It's a 30yd cast with 1 sec cooldown, it is *not* intended to be "fire and forget." Same thing with SGE's Kardia. You're meant to spread that shit around.

I do think that DNC needs teamwork more than most classes, and I do think it has a fairly high skill floor. If that doesn't sound like something you want, go play BRD instead.