Almost all MMO games, crafting items is currently not nearly as profitable as it should be. Many players begin with games and haven't reached the level cap yet, and those who did most likely can craft much of the items on their own. Shortly, crafting is profitable if you're level 50 with a maxed profession, but otherwise it's just a drain on your platinum. So does it in RIFT.
But why? That’s because most players can't afford to constantly buy new items, and so many qiests are even not necessary. The only items worth of buying while you're leveling up are weapons, especially two-hand weapons and bows since there's a shortage of them from quests, and they boost player's damage output significantly, unlike most other gear. That alone makes weaponsmithing a lucrative crafting profession and armorsmithing nearly useless.
If you do pick any of these crafting professions I as the veteran of MMO games recommend having Runecrafting as well, because it will allow you to Runebreak items you don't need or can't sell for other materials. Runebreaking is very expensive to level up since you won't be selling items to vendors or players but rather destroy them, however, once you reach level 50 it will be extremely profitable. This is in part due to the fact that players of lower levels are constantly upgrading their gear and it's not worth upgrading it with runes.
Basically it's currently hard to make significant amounts of platinum in RIFT with crafting professions. Most items are hard to sell to players who are just leveling up.