I saw and did not know which circle this was in.. I do not have subs, and in general have little interest in 'extra' or super bass anyway.
I am not raining on the parade i hope.
I voted none. as i do nothing much in any of the ways listed.
My Magnepan have OK bass, and as I live in an apartment, I do not want a whole lot of bass going intothe walls anyway.
To 'correct' my bass so far i have used Pangea powercords. which help, and fooling around with different ones. that alone is enough to get my bass Ok and natural, to a little less than typical in these bass crazed days..