This is just a bad design choice. Three actions to turn off sound when you are usually rushed (embarrassed by a call in a meeting or movie or dinner)
Should have options for different modes:
Normal with sound for ringer and media, vibrate optional
Quiet mode with sound for alerts but no ringer, vibrate optional
Silent mode without sound at all, vibrate optional
Still mode without sound or vibrate
And the front button should toggle between two of those modes.
Forget OS options, why is this not done using an application?
The tie-in to calendar to silence the phone on schedule could be nice as a OS option, I may have to try those applications out.
Same with emergency numbers that are allow to ring or alert.
Maybe a optional rule to turn on ringer if a call is unanswered three times in a two minute period? My wife and I use this as our emergency signal (but she usually forgets it and I end up stepping out of a meeting). Sorta like the remote turn-on ringer application but without need for a computer to remotely trigger your phone.