No. How much money you make has a large random factor to it, based on the opportunities available to you. Your goals should be things you can control, otherwise you're setting yourself up for frustration and disappointment.

You're better off setting goals in terms of the specific actions you can take, eg. having finished X project by age Y, or learned A, B, and C skills.

No. Be good at what you do, be smart with how you invest. If you set such a goal I can assure you that you will not perform as well as if your goal was learn X by age Y, or something similar. Money is an arbitrary and (IMHO) poor indicator of a successful life.

Depends upon what actions setting that goal lead you to take. Does it induce you to save regularly and well? Probably good.

Does it talk you into taking a job which burns you out or involves you in morally dubious activity? Probably not.

X% of Y salary per year. As your salary grows your savings have to grow.