I agree. It used to really bother me. I was always looking for one set up/paint/etc. that would do everything. Then I realized how dynamic ABing is, esp. with the interplay with all the variables. No one brush would do everything or be better than every other (though some really come close IMO), and no one line of paint was 'the best'.
It then became a matter of what did I want overall the brush/paint to act like and what did I want as a final result. Then it was simply learning to use the brush, thin the paints, etc. to get the results that I want.
I like to spray at much lower pressures, and have very fine control (using iwatas), but to do this, I had to get used to manipulating my media, understanding how each of my brushes acted at certain pressures, distances, etc. (i.e. pressure drops, use of MAC valves on the fly, etc.).
I do think there is a difference between using an airbrush as a spraygun (paint blaster) and using one more artistically. For the former, you need very little control over the variables to assure outcomes. For the latter, you need a little skill/experience, but its not hard to pick up. It takes practice, a tolerance of bad outcomes and a willingness not to give up! :)