I agree the audio rubbish that cabin crew throw at you these days has gone beyond a joke (I recall recently a BA CSD taking the entire aircraft through the procedure of filling in a Visa Waiver form on departure from LHR to JFK ffs...) however you shouldn't underestimate the positive effect on passengers that comes from a relaxed, confident, authoritative message from the sharp end saying "welcome aboard, take note of the safety instructions, we'll be on time and you're in good hands." Cover that off, and there is nothing else necessary.