Now this is a great post...
My Esoteric A-03 sounds best when it's on for 24 hours so if I plan on spending an intimate day with the system I turn it on the day before. And I have no idea why this is, but it definitely is. Other wise I usually shut down completely but do occasionally leave it in standby.
I leave my Esoteric CD player on most of the time..
Tube pre gets shut down.
Theater amps and prepro stay in standby and again unless I want it sounding its best than I'll let it run some cable music soundscape or soft jazz to get the juices flowing sometime before plopping in a Bluray.
I unplug everything when I go away....