Different subwoofer settings for different albums?

Can you tell us who the dealer is please? It will help me narrow down my list of which dealers to work with.

Undoubtedly the low bass in some recordings is more pronounced than in others and the desire to get up and make sub adjustments is hard to resist!
I`m sure that most people starting off with sub`s do what I did and run them too loud. In my modest experience that tends to subdue the rest of the frequency range especially the highs. 
The best setting is where you can notice how much better the overall sound is make when listening with and without them even though their contribution sits in the background. 

Not my experience.  If a Clapton album was mixed so that the bass and drums are down in the mix a little and the focus is on the guitar, that's what you're "supposed" to hear and a sub(s) won't accentuate that if you have your levels set correctly.  If Deamau5 wants to make your liver quiver with the bass, then your subs should do that at the same settings.

Oh man.  Oh man oh man.

Subwoofers integrated correctly are glorious. 

If you find yourself raiding their gain, you probably didn't set them up correctly, and should consider actual tone controls.

Well integrated subwoofers are invisible. Find a different dealer.