Plato was the "first" modern philosopher because he divided, was the first to divide his audience into two groups, allowing for a third as per Parodites. In fact, Parodites' claim that Plato claimed nothing beyond being, no Being, begins to show us Socrates' Ethos. Socrates spoke of common sense about all. He is the first ethical philosopher: love of wisdom is not for the lover of wisdom, but for the ordinary man. I call him a scoundrel of a manipulator, but no less a philosopher.
The Topus Uranus, we must not fool ourselves, is presented as something to be taken seriously. The world of ideas is presented as a real world with full alchemical (materializing, fleshing) force. Here is the division, not a pedaogical one but a real one: the Heaven for dullards... And the category for Us. Thus, Aristotle. But even Aristotle was chained by the Platonic ethos: present thine philosophy manipulatively.
For Plato, we know this too from his dealings with politicians and kings, the philosopher' soul is a comanding soul... The human lightning rod for all of the species.
This is why Nietzsche called him sickly: philosophy is not a comanding. It is, as Sawelios rightly says, a pleasure. But it is also a soul, as Capable hints. It is the soul that immediately grasps Plato's meaning beyond his petty manipulations, that within us which celebrates mistake and is dumbfounded by the stupid's inability to grasp its counterpoint: insight, rather, understanding.
This is Plato's ethics. An Ethics of the fall of the first great sophic empire. Let us know this so that, if we decide on an ethics, it be an ethics of the preservation of philosophy as opposed to its tyranny, which leads to thousands of years of mistake made flesh. But more interestingly, this OP says aloud what no philosopher, from this very platonic ethics, has dared say. That we know quite appart from what we are supposed to know, and that we are often much to faciecious with eachother... That mistake is our offspring, not our cause or our consequence, that we mustn't let stupid people inhibit our natural instinct by letting them guide it, nor withdraw from scorn of them. That philosophy is beautiful because we are beautiful, and not the other Platonic way around.
Does this leave space for a common ethics? Why not? Let it be a derivative ethics and not an artificial ethics. Let us show them some tricks, instead of tricking them into thinking themselves us! Maybe Plato was simply tired of living amon others, had to imagine himself removed.