When mastering, after I'm happy on my high-end near-field monitors and acoustic room, I haul my studio laptop into every other system and environment I have and

When mastering, after I'm happy on my high-end near-field monitors and acoustic room, I haul my studio laptop into every other system and environment I have and tweak accordingly. (i.e. Bose Companion 3, an older JVC shelf stereo, my car stereos, various headphones including ATH-M30, cheap iPod, and Beats, etc etc etc) for this very reason... almost nobody is listening on a nice set of nearly-neutral near-field monitors except other musicians. When done, I make sure I'm still happy on the main rig. Someday I hope to be experienced enough to just know what to do though, without all the extra work. I haven't found a systematic answer yet.