All of. If you have the patience, you should level up in all the crafts. This will give you more options to craft stuff to sell, and that gives you more flexibility. If the market for Superior Runes of the Ranger Leatherworker dries up, then ctafting can go make Superior Runes of the Scholar on your tailor. Tailors make light armor which is needed by the most popular classes in the game, which is one of the reasons damask is so expensive and profitable to make. Artificers make staves which are in demand by most of those professions. The objective is to get your crafting at least up to level
