I'd like to describe the current build I've been using for quite a while.
I see a lot of people playing NBs because they gank and do the highest 2 GCD damage in the game.
While that might be fun to some, I had success with a different take - fighter-blade, that is most suitable for smallscale 2v2 to 4v4 fights (that is BGs, which I play).

The core of the build is Esoteric Environmental Greaves.
This item is has nice synergy with nightblade, because, in my opinion, NB has the easiest way to replenish resources at this moment.
It is very much anti-meta item, since most of the sorc's damage is direct damage, and they need to align everything perfectly to hit multiple times in 0.3s window (only first hit gets 50% reduction).

Backbar is greatsword, Nirnhoned, Wretched Vitality, to fuel both stamina bars (so I have esoteric protection up even when I spam a lot), and to give mana for emergency heals & cloaks.

Body set is Marksman's Crest. It slightly increases bow damage (almost all damage skills in this build) and reduces stam costs of all skills by 5%, while also having 2 rows of stam recovery.

Front bar is Vateshran's Perferted Bow (Point-Blank Snipe), Sharpened. It buffs snipe damage, from 5% at range, to up to +33% point-blank.
Buffs one of the core abilities damage is very significant, if you are able to spam channeling in close quarters (it's interruptible) - it is gonna be painful.

Atronach mundus, x2 infused x1 bloodthirsty jewels of weapon damage (278+278+174 = +730 wd base), all armors are Well-Fitted, x6 med x1 heavy (mythic), Lava Foot Soup-and-Saltrice, Alliance Battle Draught (Major Brutality source).

It has 26k health, 15k magika, 25k stamina, 5.5k wd (bow bar), 1.9k mag recovery, 3.7k stam recovery fully self-buffed.
Access to both minor/major expeditions gives 145% movement speed walking, 145% + 40%(sprint base) + 12% (medium passives) - 1% (heavy downsides) = 196% movement speed sprint, 200% is cap.


Now the most interesting part, skill set. I use 3 scribed skills, and they play out perfectly.

Front bar:

• Lethal Arrow - does a lot of damage, procs Poisoned + Minor Defile. 0.8s channel, so next instant skill can start in 0.2s in the next GCD, for both to hit at the same time.
• Wield Soul with Stun, Anchorite's Cruelty, Major Defile. Usual follow up for snipe, Soul can go for 28m (range for 28m is increased in PvP), so it is a LOT longer range than what bow has in Scatter Shot variants at 22m.
• Vault with with Immobilize, Hunter's Snare, Expedition. Not only it will move you out of melee range instantly (allowing to push several point-blank snipes and then cast this), it will also apply immobilize and snare. Snare persists after roll, 40% for 5s. Source of minor expedition buff for 20s. And also backflip animation rocks.
• Acid Spray - perfect follow up for Vault, as they would need to roll after Immobilize, AoE damage will damage through the roll. Awesome tool against NBs. This morph is rarely used in PvP, because bombard is more annoying, but hey, with even more annoying Vault it makes this morph much more reasonable. Damage is buffed by bow Hawk Eye passive, and at high stacks this spammable does pretty much Merciless Resolve damage in 5s.
• Relentless Focus - go for more WD option, I rarely use it much for burst. At high stacks of Hawk Eye, point-blank snipes do almost as much damage.
• [ULT] Toxic Barrage - Applies very heavy pressure on top of DoT+defile pressure. Biggest outplay scenario: expect a stun move and cast it right before that.

Back bar:

• Siphoning Attacks - this thing recharge resource bars to full in several casts. Yes, you can't do that while being pressured, but if you LoS - you can. Passively, it adds a good layer of HoT and some resources back.
• Healthy Offering - you don't use it much, but when you do, you want to heal deep no matter the cost, and even blockheal if needed.
• Torchbearer with Healing, Gladiator's Tenacity, Evasion. It has the same tooltip as Resolving Vigor, but in 2s instead of 5s, costs twice more and slows you down while you do the channel. But, you can cancel it after second swing and start a new channel immediately, as it's a new GCD, effectively doing swings faster. Two swings of torch roughly equal 1 burst heal numbers, but you are doing in in conal AoE, and with the benefit of taking 30% less 2s after cast. All this in stam, which we have in abundance.
• Refreshing Path - Major Expedition source that reapplies (for total of 14s major exp if the fight is in the same place), that also heals, that also applies to allies, that also provides Minor Endurance and Minor Intellect (all those buffs stack multiplicatively, it is actually a huge boost).
• Shadowy Disguise - Shadowy Disguise.
• [ULT] Soul Harvest - Passive 10 ult/kill for being slotted on either bar.

Is this build broken? Well, no, and it doesn't kill the ward sorc 1v1.
But it doesn't fold fast either, and in a good group this build is persistently annoying and hard to get rid of, while also puts a lot of pressure tools on the table, and can even act as a group healbot due to torch.

Probably my favorite build to pilot nowadays.