Honestly, all the professions are pretty well balanced. It just depends on your personality and what you want to do. Alchemy's perks you need to use a flask to get of course, which requires a continuous input of either gold or time to gather mats. Tailoring is pretty much set and forget it until you get a new upgrade, which can definitely be convenient. One thing to keep in mind is that Alchemy's is a flat stat increase, where as with tailoring you have a random proc for a particular stat. So, you never know if you're going to have that line up with blood lust or any other buff. I'd much rather have a constant stat boost or an on use proc than a random proc for raiding, but otherwise it probably doesn't make much of a difference. Tailoring does require a lot more time/money though. I leveled up my Alchemist's prof at the beginning of Cata and it went pretty quickly and cheaply. Tailoring I didn't do until about 6 months in and it seemed to take forever.
Guild Wars 2, Crystal Desert server:
Inga Freyasdottir, lvl 40 Norn Mesmer
Deathbringer Kaami, lvl 16 Asura Necromancer
Popina, lvl 15 Asura Elementalist
Althaia Willowbark, lvl 7 Sylvari Engineer
Maeve Amnell, lvl 4 Human Guardian The MMO-Zam's FB group.
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