I guess all of us here play(ed) ESO mostly as a single-player RPG, at most doing some world events with random people, or play(ed) it in co-op. We mostly ignore(d) the PvP content at all. All my previous experience in the PvP area (Cyrodiil) was meh. That area is too huge for my liking. However, about 2 weeks ago I tried the Imperial City. And it changed my view on the game forever. The Imperial City was once paid DLC, now it can be activated in the Crown Store for free.
Unlike Cyrodiil, it's packed and very action-focused. It consists of sewers underground areas and several districts on the surface. While you are in the Imperial City, you gain special currency, Tel Var Stones. Killing any monster there gets you a certain amount of that. The more of them you have, the better modifiers are to get more Tel Var Stones for killing. The tricky part is that if you get killed, you lose 1/2 of what you currently carry. You can store as many as you want in the bank, and those stored can't be lost. You can buy special sets for Tel Var Stones, as well as other special rewards.
Also, monsters in the Imperial City drop special Vault Keys. When you have 60 or 150 of them, you can open special Vaults to gain good rewards, including motifs and styles. You can't lose the keys when you're killed.
Each surface area of the Imperial City has its own Daily Quest. It also has its own equivalent of a World Boss or a Dolmen. But any activity there goes with a risk of getting exposed to players of the opposite alliance. Even opening a locked chest can be risky. So essentially you're playing on the edge.
You can use Sneak against enemy players, and there are ways to counter other players' Sneak.
However, what I wanted to highlight with this post is not how fun (or unfun, if you don't like dying to opposite players much) the Imperial City PvP zone is. It made me understand the game mechanics better and finally get a good grasp of what each role (Tank or DPS) should have, why, and how much. When the game puts you against other players in not a huge area and gives you all the means necessary to use your surroundings (to sneak) and your skills to the most effective result, it explains things naturally, and much faster than any Trial/Vet Dungeon with random people can.
For example, I now understand and use the method illustrated here:
I now understand what I should go for on any character concept I have in mind, and why, be it Penetration, Crit Chance, Crit Damage, Weapon/Spell Damage, what Mundus Stone should I use, and why, etc etc. I understand differences in using different sets and skills and what that leads to.
A small illustration: there are means in the game that make your next attack a Critical. If you max Crit Damage and manage to sneak up on your opponent, you can essentially end them in seconds. Or, just the opposite, there are ways to counter Crit Damage and increase your Health pool and Health regen by a big degree.
I've had more than 1k hours in the game before. But only now I understand finally what some things do and how to perform them. It all helped tremendously in evaluating some challenging PvE content as well. The lessons learned in PvP answered so many questions regarding normal PvE gameplay, be in World Bosses, Dolmens, Dungeons, and more. I understand better what other players do in combat and can evaluate how I can help them more in standard content. E.g. I understand if normal attacks inflicting 4k damage is ok, whether ~8k damage is big, whether a crit of ~15k damage is great, is a pool of 24k HPs big or not, etc.
Overall, games and their features can surprise you. If you try them, you might be positively surprised, even if the first reaction is "No, thanks".