I agree, although even vibrate is too loud for my tastes. The biggest win of having a watch connected to my phone is that I can leave the phone entirely mute with the vibration off and get my alerts through an actually discrete vibration in the watch.
I agree that for example when the phone is on a table or on a hard surface vibration can get really loud. Having it on your wrist it makes perfect sense
That said, these ring tones are better than most.