Do you create multiple toons and have each of them specializes in specific tasks?
For example, for me, I play 3 toons as main, all reached max level and properly geared up:
This allows me to always have the most optimal build for each task (and for my play style), without having to re-trait myself every time. Why those three professions and not others? Because I enjoy them the most, of course, especially the elementalist and the thief. 
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