The fastest way to level is through crafting. It's also the most expensive way to level. Each craft will give you a guaranteed 10 levels for maxing it out.
Maybe I am just a "money over everything" kind-of-guy, but I have always thought crafting was the worst way to level. If you are going to max a craft or two then go ahead, but if you you are going to max a craft AND go 100% then it doesn't really matter how you do it.
Gold sinks to level is a bad way to go. Lose money (if you even have enough (i.e. first character.)) And soooo boring.