The only traits that see any use at end-game are Divines, Infused and Impenetrable for armour and Infused, Powered, Precise and Sharpened for weapons. That's only 7 out of 16 possible traits, less than half of what we have. Perhaps the 9 that aren't used as much could be improved? I'm not saying all traits should be useful at end-game, but having more viable choices would definitely be nice. Here's some suggestions:
Armour Traits
Exploration - Obviously meant to be a leveling trait, but could do with a bit of a boost. Perhaps it could also increase gold gains from drops and chests.
Reinforced - IMO the problem with this is more of a problem with armour in general, and probably doesn't need a buff if those issues are resolved.
Sturdy - A new effect for this one. Maybe something tanky, to do with blocking (might be too much with what we already have) or healing received.
Training - A leveling trait like Exploration, but I think could be improved by making the bonus to all experience gained (with reduced numbers of course).
Well-Fitted - Allow it to also reduce the cost of dodge-rolling.
Weapon Traits
Charged - Not useful at all. How about a new effect, say a small chance to gain bonus Ultimate.
Defending - As with Reinforced, I think the problems with this trait is more to do with how armour and spell resistance currently works.
Training - As with the armour version, I'd suggest this increase all experience gained for a lower amount.
Weighted - If animation cancelling is fixed, then this trait may be viable. If ZOS has no intention of fixing it then this needs a new effect.