Boosters will not make a difference for experience gained through crafting. XP boosters are for killing monsters, crafting boosters grant additional "crafting" experience. You may level up a profession faster, but it ultimately has no effect on boosting real experience.
You get 10 levels for every discipline regardless of what level you are when you level the discipline, or if your leveling of the discipline is spread across multiple sessions with other leveling in between. That also means that you get more effective experience from disciplines from 70-80+ (or just 80+ for skill points), but it still allows you to get 80 levels from leveling all 8 crafting disciplines. As Absintheminded said, boosters don't affect the amount of experience you get from crafting, but crafting boosters will make crafting cheaper and faster.
Jewelry and Cooking are significantly cheaper than any of the other professions due to the fact that all 6 other professions share the same mob-drop mats. Cooking was less than 2g to 400 however you need high areas unlocked to buy the karma items (buy them from an alt or just craft as you level). Jewelry is just dirt cheap, even profitable if you already have most the jewels and only need to buy ore. I have all professions at 400, have done a few of them multiple times and pretty much every one of my characters has jewel/cooking as well as their main professions :P
note: Jewelcrafting is not worth doing 375-400 if you are only interested in exp. It becomes majorly expensive. Likewise, all other 6 professions (exc: cooking/jewel) 225-300 seems like a cock block because the mats in that tier are so expensive.
Last edited by nightshark; 2012-11-27 at 08:03 PM.
I leveled from 30 to 80 for about 6g in around 2.5 hours, and I put bids on all the mats I didn't have, granted I did have a lot of things pooled up in my collections as it was my 4th 80...but yes, it is totally doable.
Edit: I did Artificing, Tailor, Cooking and Weaponsmithing if you're curious.