Good earplugs will keep some of the PAs out (although unfortunately many of them are done before it's sensible to put them in). The Top of Descent announcement often serves as an alarm call for me, maybe because my brain is expecting it and knows that it has to wake up - but I do sometimes manage to sleep right through until the cabin crew are securing the cabin for landing.
The extent to which DVT videos are being shown - undoubtedly for legal liability reasons - is getting ridiculous. I've become used to seeing them on SYD-CBR flights, flying time about 25 minutes.