Once you got your alchemy to the point of 300/ 300 alchemy you are ready to make the big bucks.   The goal once you have 300 classic alchemy is to start producing each of the bottle neck items needed to make mounts.  Those items are

- Arcanite bar- Needed to make classic the Sulfuron hammer  , Arcanite Champion and other fancey Craftable items.

- Living Steel  - Needed to make Panthers and Sky golems

- True gold - Needed to make the only flying craftable two seater mount usable at level 30.  The vial of the sands.


- Titanium- and Titansteel Bars - Needed to make the only 2 seater craftable land mount - The Mekgineer Chopper and Mekanohog.

Controlling the bottlenecks lets you control the markets.
Control Living Steel, Titanium , Titansteel, Arcanite Bars, and truegold   You control the big boys in the game.

But you can make big bucks selling the above transmutable bars without much work.