I am going to say this it is interesting and incorporates other items of the game like the Monstrology. But the (there is always a but)... I see one weakness there are some players that do not do Fishing or Monstrology or any of the other items except the worlds and the pets. Some people simply do pets with a specific toon and other items like fishing with a specific toon and crafting with another.
So to balance (no pun intended) all the possibilities I think the idea needs to be fleshed out more for KI to evaluate.
Well why not include the crafting in the Questing of level up. To make them craft or fishing is the only solution to include this in the quest's, Make a Crafting world so that they have to craft or fish, otherwise they can not level up to reach the next world.
What I most like is Puzzles next to the Spells to fight like eh for example:
You cast a Puzzle Spell on the opposite and that spell ask you for example:
What is the short symbol of a Sad Face answer is :( , or, What kind of reagent do you need to transmute a Diamond? Answer is Ore.
How good do you know this game? A sort of brain game inside the casting spells or quests.