This system seems problematic for base-level (i.e. assessing murder, theft, etc.) morality. This is because of the limitations of "similarity." We would not want a system that treated all murders as essentially the same. We want one that incorporates certain exceptions. Those exceptions may be "he was trying to kill me, so it was OK that I murder him" or "she did not prove to be a virgin on her wedding night, so I rounded up her brothers and we stoned her to death." It seems like you need a reasonably well-defined parametric morality before you are capable of saying which situations are "similar" and which are "different," since we don't think "She lied about being a virgin" is sufficiently different from the null to merit separate treatment, where "He was trying to kill me" does merit separate treatment.

Though trying to condense morality into singular propositions seems ineffectual. Morality seems to serve many functions, and it deals with vastly different events and behaviours, so assuming a single maxim can properly capture all of morality, or even much of it, seems wrong, or at least unreasonably error-prone.

RH's "People should get what they want..." is the perfect example of this. It's really incredibly weak (in a technical sense), as it says nothing about cases where people do object in any way, and it doesn't even say something about all cases where they don't object ("usually"). It would be much better described as "value demonstrating libertarian belief system" than "universal moral code." It seems like it is a principle at the core of a libertarian ethics system and not present in almost any other ethical system, but it is totally ineffectual at condensing morality, given its tremendously limited scope.