(Just an idea) (tl;dr at bottom) (important stuff bolded as well)
This is a suggestion I have based on my previous MMORPG experience:
What if all armor, as well as upgrades with tempers, had a range of values rather than a specific value? Traits would stay the same, but attack would increase or decrease within a certain range at random. Think about a game like Maplestory: If anyone has played that game, you know that the quality of your armor is what makes you competitive/what people are most proud of. This won't be completely true in ESO, because ESO also puts massive importance on game sense, build quality, and personal skill, but the system will add an extra level of competition to the game, and imo makes it more fun. Additionally, I think it would go well with the One-Tamriel system of Bind-on-Pickup for much of the gear, because it adds more customization to the player's armor, so that people are more motivated to keep playing to keep getting better gear, as well as a more competitive armor market with a more dynamic value for each armor piece based on its individual stats. This would also increase the value of being a master crafter, so that instead of getting that for personal use and catering to people's specific tastes, the reward for becoming a master crafter would be the ability to make items of high quality such as this (maybe a passive would increase the chance of a high deviation, for better or for worse), and then sell it to people at a competitive price.

I mean, this is the *** U.S.A., the best planet on Earth- and ESO needs CAPITALISM!

Implementation: When you craft or pick up a staff, for example, let's say it normally has 1000 attack. Now, when you get this staff, its stats range from 800-1200; Though this is a massive change, 90% of the time, it will remain within 900-1100, and the further it deviates, the rarer it becomes. Then, if upgrading the item with honing stones to make it a green item usually brings it from 1000 to 1200, it would instead bring it from 1000 to 1100 to 1300 (or from a 1200 to a 1300 to 1500). This would keep going with all rarities.

Maplestory had this fun mechanic called "chaos scrolling" in which with a 60% success rate, every stat on the item would go up or down anywhere between -5 to +5. This is crazy, and anyone that got lucky with one or two of these scrolls would be celebrities; their items worth ridiculous amounts, and everyone would be trying to one-up them. Scrolling is a cool mechanic as well, but I don't see how it would work in this game... If it could, I would be all for it (maybe scroll armor for (max or raw) stamina/magicka/health? or scrolls add a random effect/weak passive?) My real point in bringing this up is that Maplestory is a very social game, and part of the reason for that is this armor customization mechanic. Being able to not just compare raw dps with someone, but also your gear, is more fun than it sounds. Buying the right gear for yourself, or working to make it, made Maplestory fun to me back in the days it wasn't a pay-to-win clusterf*** of classes...

tl;dr we need more armor customization so that crafters and people who work for their armor can be rewarded with better armor, so tat there is more demand for armor and another way players can compete with each other, and that master crafters can reap the rewards of capitalism and sell their armor to the highest bidder, rather then get called upon by obnoxious people in their guild to drop what they are doing and craft them a set piece...

thoughts? did anyone actually read this all the way through?