Are you as tired as I am from hearing about elitism and "Best in Slot" chit-chat and put downs? I love the amount of sets that are out there - but I honestly don't think there are enough abilities for people to choose from to suit their style of play and reduce the "BiS" elitism that seems to dog each and every MMO.
Here are a couple of suggestions that might stop this happening... and start to mean we see different builds out there, rather than everyone copying the same few builds...
1) Create a few more traits to learn with 10+ trait craftable armor
2) Give more morph options to skills (like 2 stamina morphs and 2 magicka morphs per skill)
3) Create more skills for each class
4) Introduce at least one new class and one new race
5) Racial active skills - as well as passive ones. Let's see Orc's have a "beserk" active ability or Wood Elves getting a long range bow attack etc...
6) Greater selection of enchants and runes
7) New guilds - and pit guilds against each other (Blacksmithing Guild, Traders Guild etc...) And start to force people to have characters make choices about which guilds they want to join - and don't allow certain guild choices coincide with other guild choices. Let's face it, no thieves guild in all of Tamriel would accept a Dark Brotherhood member among them.
8) Farming/Harvesting/Crafting sets. Bonuses that speed up harvesting - or even increase the amount that can be harvested. Maybe even sets that show the percentage chance of a node dropping a special inclusive farm (like nirncrux - or maybe even, as suggested, the trait stones of extra trait(s)).
I'm excited for One Tamriel and all the new sets... but I think ZoS could go a LOT further....