You do realise that the recipes are also based off the price that there is already an implied xp for each resource item.
This is another example of someone saying, lets have exactly the same system, but change a couple of variables - but, into the deal you have to rework everything!
xp depends on the price, speed of crafting depends on the level - by changing those 2 variables you can create exactly the same thing as suggested here without having to redo everything.
Now, those things are *if* it was desirable to change the xp-ing rate for crafting, which I am not convinced of. Crafting itself is a supporting system, to allow you to either make money or arm yourself to take part in levelling in PvE or PvP. It isn't meant to be a serious way of levelling, its a slight bonus as you go.
We want people out interacting with each other, levelling as you play, not playing to level.