2. Yes, this is where I would push back because one can also assume there is no "better" basis in the strict sense that you can intellectualize morality/virtue only to a certain extent. And it is possible to argue that morality/virtue is often as much a psychological process as a purely intellectual one. So the idea isn't that the golden rule doesn't make sense or that it is objectively weak, but it doesn't map to the idea of actual morality in action. For example, a person may logically believe in the golden rule but that doesn't mean we should ignore the fact that the agent is not fully logical and will not always strictly adhere to a rule just because it is aware of it and aware of it as being Good. In that sense, what use is the golden rule if we are free to ignore it at all (which we often do)? That doesn't mean I'm saying the golden rule is objectively wrong again, but in ranking morality and deciding on very abstract ideas of what Good and Bad are, we ignore the actual psychological forces that are extremely relevant when it comes to the execution of morality in action. So to answer the question, the better basis would be to understand the psychological forces behind why we feel the golden rule is objectively a good and then examine them to understand if we are following the golden rule because we actually think it is good or because we live in a society where it is good and we will be shamed if we don't believe it. One might say it doesn't matter as long as people actually follow the golden rule but another interpretation is that the golden rule by itself doesn't tell us anything (or very little) about the moral character of the person applying it. So just expecting people to follow that rule after knowing it is placing too much trust in the human animal who is often wild and not thinking logically. It is then upon the animal to tame itself and it may do so out of servitude or out of independence and both might lead to equivalent surface values and match the basis perfectly as being morally good while in reality, both have very different meanings for their morals.
2 is, of course, mainly inspired by Nietzsche. I'm working on a short story where he and Plato debate whether a painting is objectively good or bad called A Canvas Called Virtue.