One major thing I really hate with progression in MMOs is when gear gets “out of date”. In wow for example, current expansions offer armor-sets with different and unique set bonuses.
However, the next expansion increase the lvl and also make your gear outdated.
ESO solves this somehow with making all gear-sets a functional different from eachother (instead of Stats). So each gear set have a unique bonus that affect your abilities. In New World, this could be a gear-set that increase DMG reduction from tank aura, or a trapper-set that let musket users become great CC with their traps somehow, or may add another layer of effect on abilities.
This also means that people farm gear-sets just in-case they wish to respec into another “ability-focus” playstyle later on. Win win 
what do you think and what would you like to see?