So I currently have Enchanting/Jewelcrafting, and I'm thinking I should drop one for Engineering. My issue is I have all the cuts for JC and save myself a lot of gold by cutting my own gems and disenchanting has gotten me a lot of gold from selling crystals on the AH.
Is the profession worth it for an enhancement shaman if my guild is working on heroic modes now?
I don't think it's worth, it might not be the ultimate min max but your profs are really good already.
Engi is more about perks but is still best min max (on demand prim stat boost + off the gcd bomb belt).
BS is the most flexible.
I have alch+engi and very happy with the combo. 2h flasks and instant bank/repair access as well as transporters. I had JC earlier in stead of alch, but really disliked it (JC dailies and such), switched start cata and never missed it (although i have JC on an alt).
Herbing is simming as the best proffession. It's value appears to be greater than the next two profession combined due to the ability to line the CD up with other stuff. Combine with engineering you will get every other engi glove lined up with lifeblood which has a synergistic affect (more agi increases the DPS per haste point and similarly each haste increases the value of each agi).
Engi bombs just throw it completely over the top. They never fail unlike the boots.
Engi gliders have also had some useful moments this tier (getting nest to nest without a feather, the Durumu knockback that happens during the stunned life leech, etc).
I've always enjoyed Engineering on my Shaman characters. The CD for Synapse Springs lines up pretty well with our other big CDs, allowing a good amount of burst. Already having two other maxed professions makes it tough to decide. If I were to keep one of what you have, I'd probably keep Enchanting (as it's harder to level imo, and you can make a lot of money through the AH, as well as it being useful) and then drop JC for Engineering. I tend to spend less on gems than I do on Enchanting mats.