This is how the basics look like. Simple? Yes, that is the beauty of it. This type of portfolio have been tested in different countries, so it is not specific to US or other.
It indeed looks simple, but imho one has to have
at least 500k, but most probably more than 1M USD worth of wealth in order to get even close of thinking to diversify like this.
But maybe I am wrong and then I am open to suggestions.