After you reach a certain value on your stats, further progress no longer pays off. As has been argued before, at that point there is literally nothing else to expect from the game - you've reached your character's peak condition, and you're staying there forever. Pvp'ers can still compete with others since their stats are more directly comparable and they have immediate feedback for their grind, but that's not the case with most others trades. How does a crafter or a cook compete?
Moreover, a player's personal style is important in pvp, but equally-statted crafters are exactly the same: they are not unique in any way.
The suggestion is that crafters become of more strategic value in the game as a whole.
After reaching their endgame status, a further list of skills should open up to the players. These skills should be limiting and mutually exclusive, that is: they should require a very large amount of XP and LP (as well as high lore, carpentry or smithing etc, related to the selected skill), and choosing one of them should mean the player forfeits all the others. In essence this is a specialization that represents the result of a lifetime of work.
Purchasing them would give the character the ability to craft unique items, as well as to give them names. For example:
Master armorer: craft silver and golden armors
Master cook: fancy cakes, shewbread or some such
Master builder: build variable texture stone walls (for aesthetics only)
Master painter: ability to mass produce simple sketches.
Toymaker: recipe for one new curio
Weaver: craft clothes in unique colors (yellow, red, purple)
Shieldsmith: different shield formats (norman, square, buckler, tower)
Swordsmith: silver sword, etc.
Gardener: once a week, plant a seedless purple/black/rainbow-colored flower
Treeplanter: once a week, plant a seedless exotic tree.
And so on
The goal with this is to make an endgame crafter's products a bit more valuable and unique, hopefully creating minor industries in the process and also improving specialized trade. Another point is that this would give non pvp'ers a reason to keep grinding.