Something else for people to grind for, when they hit the cap. Sort of the whole apprentice - journeyman - artisan - master. I'd love to see capped crafters be able to install weapon effects such as vorpal, shattermantle, banishing etc. We've always been able to find these effects at various levels from ML1 over the years.
Grinding how? You haven't suggested more levels be added, or that you would have to do anything more, just that a whole extra type of crafting or two be handed only to people at the cap.
It makes a lot more sense for new recipes to be added as we level, with the best saved for the highest levels. Not no crafting of this type until you've maxed out.
If our existing system worked the way you've suggested it would be an absolute dumpster fire. Why change the paradigm?
It looks very much to me like you're suggesting it be made overly restrictive so you can be one of the very few people who could do it. I've seen this sort of selfish, gatekeeping behaviour towards crafting in another MMO before. I didn't like it then and I don't like it now.
The majority of the community would far better served by a system that was more widely accessible, not one that supports individuals or cartels of people actively making things harder for people coming up the ranks below them. You know, by them advocating for things that help them above anyone else.