My VR16 magicka nightblade plays three roles in one character, carrying around different gear for each: DPS, healer, and tank (DPS/healer in light armor, tank in heavy). I haven't tried stamina-based tanking, but the magicka nightblade tank is very, very powerful and is, IMHO, one of the best tank types in the game because you're a tank that can also dish out a ton of damage.

I went with 5H, 1M, and 1L for the undaunted passive. Medium bracers and light belt so that I lost a minimal amount of armor. Sword and board on both bars (I dual-wield Torug swords for my magicka DPS setup for the added spell power, so I share these swords with my DPS setup).

As for armor, I prefer Whitestrake over Hist Bark. Hist Bark grants Major Evasion when you're blocking, but as a Nightblade, you already have a class ability that grants Major Evasion, and fully ranked, it lasts a pretty decent 26 seconds. Yes, it's a hassle to switch to your back bar now and then to re-cast it, but Whitestrake has saved me many times. As a tank, you're pretty much safe as long as your block is up. What you need is something that can protect you if you get in trouble and your block isn't up, such as when you're resurrecting someone or when you are out of stam to block. In those cases, you'll be happy to have Whitestrake.

At end-game, my gear is 5p Whitestrake, 2p Torug (I also share a Torug armor piece with my DPS build), and 2p Engine Guardian (really, it's the best monster set for a tank). For jewelry, I use either 3 pieces of arcane Willpower or 3 pieces of Footman, depending on the situation. I don't use 5p Footman. In most situations (including all "legacy" vet dungeons), I use the Willpower jewelry because it gives me a lot more DPS, but in some fights where I'm under more pressure, I'll use the Footman jewelry instead for the extra health and resistance.

As for abilities, the key ones that I use are Siphoning Attacks for resource management, with Sap Essence and Funnel Health for my main attacks. If you have Caltrops, they are awesome because they aggro enemies to you and help proc Siphoning Attacks. Veil of Blades is my favorite ultimate, though Barrier is also nice if you have it. I personally prefer Summon Shades instead of Twisting/Refreshing path because it's cheaper to cast (I want a cheap Shadow ability that I can cast for the barrier passive, and Shades is not only cheaper, but a 15% damage debuff against a big scary boss is a very nice thing to have). Blur and Impale (my execute) are also on my back bar. When ranked up, Defensive Posture grants an 8% bonus to block cost and mitigation just from being slotted (I rarely cast it because I want to conserve stam--I just keep it slotted). Absorb Magicka (morph of the light armor skill Annulment) is also a great skill to slot in for certain fights. It's a very cheap and large shield that protects against "spell" damage, which is pretty useful in a range of scenarios. Almost all the damage in the final boss fight of VCoH is spell damage, for example. When you go farming for your Engine Guardian helm, all the damage from the final boss itself (including the poisoned air) is spell damage (that skill helped make my 30 or so runs of VDSC bearable).

I'm a Breton, so I have some helpful bonuses to magicka. I don't have many CP, either--only 175. At VR16, with my purple food buff active, I have 30K mag, 24.5K health, and 16K stam if I'm using my high-DPS setup (1824 unbuffed spell power). And with my studier setup with the Footman rings, I have 24.5K magicka, 27K health, and 18K stam. It doesn't matter too much if you get your stats from attribute points or from gear enchants. Just as long as you have enough health to stay alive, enough stam to block, and enough magicka to do damage and do other stuff.

Now, I'm not sure how useful all this is at VR2. I started out as a stamina nightblade DPS, and didn't switch to magicka until VR8, as a dps/healer. And it wasn't until much later--around the time I hit VR14, if my memory serves--that I finally had enough skill points to add a gear-swap tank role to my character. So I've never tried tanking at VR2. If I were to tank at that level, I might consider using the Unassailable set. It's a pretty decent tank set with lots of healing-received bonuses (magblade saptanks are centered around their self-healing) with 3 pieces of jewelry, so you can use that as a stand-in until you reach the end-game.

http://forums.elderscrollsonline.com/en/discussion/218683/the-new-bloodknight-nightblade-tank-post-ic-pve#latest

This is what I have.