Re: $1M a year — is that a lot?
A simple first step towards more tax fairness would be to ... . A fairly simple second step would be to ... . System is simplified and no rate changes needed
With respect, I don't think you, or I or any other commenter here could design a useful and effective tax system. "Simple" tax systems tend not to work particularly well. And governments also use tax systems to "nudge" people into behaviours they want. For example, maybe the government think NFTs are a waste of society's resources - so they tax NFTs more heavily. Maybe they want people to invest in "war bonds" for an emergency they are expecting - they will often use the tax system to do that.
That isn't a problem. Complexity isn't really the problem. As long as it is progressive and there are not significant loopholes. I don't care whether the tax rate is identical for earned income over $10M and investment income over $10M. I care that they are both high.