Necromancer, for me.

#1 reason is because I just like necromancers in my RPG's. All my TES characters are some form of necromancer, and a necromancer will always be my first character in games where they are an option. ESO didn't launch with a necro class, so I didn't create mine until I returned to the game in December and picked up Elsweyr, but my necro became a tank. I would have been a necro tank regardless.

But what I do like about it after playing it, is that the way necro abilities work, I can be a little bit more of an offensive style tank with a Necromancer. By no means am I any kind of dps, nor am I trying to be, but rather I can add a little bit more of a punch than is typically expected from a tank, and I've been able to do so without sacrificing my tanking priorities.

My current setup:
40k+ health (will be increased when I re-adjust some traits)
max resistances
10k dps parse (tho would be lower than this in actual end game content where I am no slotting as many dps abilities)

Monster Set: Lord Warden or Balorgh
Armor Set: Leeching Plate
Weapons / Jewelry: Akaviri Dragonguard
Alternate Set: Grave Guardian
Vampire Stage 3

Front Bar: 1h + Shield, Hungry Scythe, Inner Rage, Mystic Siphon, Elusive Mist, Unnerving Graveyard, Glacial Colossus
Back Bar: Restoration Staff, Spirit Guardian, Angry Totem, Enduring Undeath, Beckoning Armor, Necrotic Potency, Ravenous Goliath

I use the Elusive Mist / Strike From Shadows combo + an Essence Of Spell Power pot to quickly boost my spell damage (when I'm solo'ing, I can get this up to around 3k Spell Damage on the character sheet. If I am doing group content as a solo or main tank, it drops to about 2500) and drop my Unnerving Graveyard right where I stand, ranged taunt everything into me, and then drop my totem. Everything in radius of me gets feared, debuffed, and dot'ed. As they die, I can then hit Elusive Mist again to draw Mystic Siphon, boosting my mag recovery and doing even more dot damage to the debuffed and feared masses. Re-apply taunts, Spirit Guardian, Beckoning Armor, Totem, and Graveyard debuffs as necessary.

My roleplay concept is to be a corrupting Necromancer warrior, cursing the ground that he walks on, and using the souls of the fallen to further fuel and power his own abilities. Lord Warden, Grave Guardian (when I use it), Angry Totem, Unnerving Graveyard, Enduring Undeath, Mystic Siphon, Glacial Colossus, Ravenous Goliath, and the Leeching Plate set all contribute to this.

It's been fun to play. Not a meta, but it is capable of doing vet content, including trials and DLC dungeons. Assuming that I know the mechs - many of which I am still learning because I am still fairly new to endgame content. But it's been fun.

I also have a Warden tank, who was originally intended to be a healer, but as I was leveling him as a healer, I realized I liked the Warden's tanky abilities as well and wanted to find a way to combine them. I was originally thinking a tanky healer, but ended up becoming a healing tank.

I'm currently running Brands Of Imperium armor and Combat Physician weapons and jewelry, so I just cranky out damage shields all over the place. When it's all firing off at once, I can fill my entire health bar with damage shields. It's been super survivable (again, granting that I understand the content mechanics. It can be a struggle when I'm still learning mechs)

Lot of people ask me why I'm running Combat Physician, but when everyone is staying healthy and alive due to my powerful heals from the tank position, as well as the constant damage shields, that confusing quickly goes away lol.