The best end-game profession is the evolution stone guild. Later on, the refiners and bowls are important for people crafting evolution stones. In the early game, players need pottery materials for their big Windstride quest.
Because the materials created by crafting guilds are valuable to players in different stages. There are lots of crafting professions you can choose in Blade&Soul, but none of them are enough to give you all the time you will need.