The following is a wall of text exploring alternative approaches to game balance you may or may not agree with, but at least it's broken up into pretty paragraphs.
ZoS must have begun this project with stars in their eyes and held enthusiastic meetings full of incredible ideas.
They will make a game with everything people love about The Elder Scrolls, but it will be an MMO! Amazing!
"Players will be able to choose from almost 10 races (and 10 if they pay more) all with unique abilities! Yes! And they can choose from one of 4 classes and have access to every weapon and all types of armour! This is unprecedented character customization!
People will be able to play any way they want!"
...Is probably what they said.
In theory, it was amazing. In practice, the problems were inevitable.
The more options you are given, the more variables you create. The more variables you create, the harder it is to find balance. The harder it is to make something work.
There are so many variables in ESO.
When skills and abilities are created with unique results in mind, it is inevitable that some will be more effective than others. But at least it gives the player a sense of being special, that their character is unique.
However, when skills and abilities are created with equality in mind, you end up with a series of bricks painted in different colours. They all cause the same amount of damage when you throw them, but mine is blue and yours is red. Players are left suspicious that what they have is just the same as what that other guy has, only it just looks different.
It is hard enough to create an MMO where the class system is rigid and only allows you to use one weapon type and wear one armour type and still find balance between them.
ESO allows players to use every weapon and every armour, with a class system that offers a whole range of skill builds. To find balance between every single combination is going to be a next to impossible task.
Having said that, what this freedom offers the player is something truly unique. And I don't think that the solution will be found tirelessly tweaking skills until the entire dev team are driven mad by the futility.
I believe the solution will be found in tweaking the ways in which all these unique combinations are utilized.
For example, currently arguably weak builds are thrown up against arguably OP builds in PvP. The expectation from the player base is that his or her combination should be able to defeat any other combination.
Given the fundamental mechanics of the game previously highlighted, this expectation is unrealistic.
However, if each class had one or two skills devoted to providing the other classes with buffs they did not have access to, suddenly every class has something to offer in a PvP setting.
There are a few skills like that now, only they are not exactly unique to one class. Anyone has access to the same buffs through alchemy, enchanting, crafting and so on.
By giving each class something that helps the other classes, PVP becomes less about going up against this or that person and expecting to be able to win, and more about combining efforts with this or that person to overcome challenges.
Everyone feels useful.
Currently in PVP we have groups of players running together throwing bricks. Victory depends on how big your group is compared to the group of enemies.
Or how big your brick is.
For PvE any build is more or less effective in battle. Some are more tedious than others, but they all get the job done in the end.
But therein lies the problem of PvE. The job. Or to be more technical, the objective.
The objective in PvE is to fight. That is the only way to progress your character. You don't earn progress levels by crafting. You only progress in the craft.
In previous Elder Scrolls games there were so many routes to character progression. Hell, you could do it by constantly jumping in one.
ESO has the foundation to provide players with so many ways for them to progress, but currently there is only one permitted; kill things.
If exp were gained for crafting, speaking, selling, raising chickens, playing music and those skills used contributed to the overall viability of the character and the way it could contribute to the in-game community, the issue of combat balance would be but a minor inconvenience to some, and become irrelevant others.
While those were not exactly serious suggestions, the point is that by opening up other avenues for players to progress, the variables are lowered simply by players rejecting those options that are not relevant to them.
For instance if it were possible for players to traverse the land avoiding combat, either by using wagons or hiring groups of mercenaries to tackle the beasties for them, crafters could find mats in any area of any grade and focus purely on their craft.
My suggestions are by no means the magical formula to the problems ESO is facing with balance. I simply offer an alternative to the way balance is approached given what the game wants to offer its players.
I'd love to hear what you think.