Take your time. Level all the remaining crafting classes to 15 for their cross class skills. You do not need Leves for this, only a pittance of gil per class and to make everything in the crafting log from 1 to 15 (a couple classes might require repeats).

Then level them all to 20, then to 30, then to 40, and then to 50.

You will also want to level at least Botany and Mining, if not all three gathering classes, in order to dramatically reduce the amount of money spent on raw materials. The primary advantage to leveling all of the crafting classes together is that you get to make your own gear, and to minimize the total amount of gear necessary. You won't be replacing any given piece until the last class has leveled past it, but this means that at most you will have two pieces of gear per slot, rather than six or seven. Keeping your gear up to date, and HQ, will allow you to craft any 70 or 80 durability recipe as you level and make it HQ, even starting from NQ materials. 40 Durability recipes are a bit harder however.

One more thing - if you craft your Leve hand-ins yourself, you not only get the experience from the leve, but also from crafting it. Since you want to hand HQ stuff in, you'll naturally be seeking to add as much Quality to the recipe as possible. That happens to be the way to maximize the experience gain per recipe, as well. The more Quality you add while making the recipe (which does NOT include the boost from HQ materials, that boost can actually cut into your experience) the larger the bonus experience at the end.