About the vibration, this is a very common problem with motorcycles and mopeds in general. I tend to use bar-end mirrors, which vibrate much less. If you can find one of the quality bar-ends that has a rubber mount, that will make a big difference.
But even the rigid mounted ones are better than a regular stalk mirror, with respect to vibration control.
If your mirror has an adjustable stalk, try changing the length - and thus the tuned frequency - of the mirror.