Die 1x: lose 5-10% sp and the same (number not % exp). This can be recovered via killing monsters.
2x (while weakened): More sp loss, gil loss.
3x: If you are in a party the other members can loot a random piece of your gear for the inconvenience you are causing them.
4x: Your lose your character. It is put up for auction to someone who can play it properly, since you obviously can't.

I'm being somewhat facetious here, but I do think there should be sp loss. As for crafters who die on the way to a leve, you should be traveling on a DoW class anyway. The story line quests need to go to hard fights that require a party, anyway, so you would need to have at least one DoW class leveled. I personally don't think leveling crafts to 50 when your highest fighting class is R2 should be a completely viable option. If someone wants to do that in a monster killing based game, the devs shouldn't go out of their way to make it convenient.