It's doing the material a disservice to ignore Legends; it's perspective on many things, especially the Force, The Jedi, and The Sith, are infinitely more nuanced and rich. The Sith in the cannon stories (Sidious, Maul, Dooku, Vader) are almost always portrayed as cartoonishly evil, with no ambition or thought beyond getting more power and stuff than they already had. Vader's really the only exception.
Compare the Canon and Legends version of Dooku. In the canon, we only ever hear briefly about how he used to be a Jedi, and his reasons for joining the Sith or starting the confederacy seemingly amount to simple self interest.
In the Legends canon, there's more to him than that. He is actually a deeply principled man, and is entirely sincere in his wish for a better galaxy. He's also deeply emotionally repressed (Blame that on Jedi training). He expresses a grandfatherly fondness for Obi-Wan and great respect for Mace Windu (Yet another figure who is far more compelling in Legends), but his ruthless ambition is so extreme, and represses his personal emotions so much, that he never allows himself to accept that he feels any connection to anybody. He uses his philosophy to cover up his superiority complex; he rationalizes his elitism, xenophobia, and racism with the Sith principal of survival of the strong.
Analyzing the philosophy of Star Wars without Legends is pointless; most of the Star Wars philosophy is only explored in Legends.
So with that, I will cast my vote. Let;s take a look at the code of the Sith.
Peace is a lie, there is only passion.
Through passion, I gain strength.
Through strength, I gain power.
Through power, I gain victory.
Through victory, my chains are broken.
The Force shall free me.
In my opinion, the actions of the typical Sith do not demonstrate the core maxim of this code. Truly, most Sith have proven too ignorant and arrogant, and like the Jedi, they are ultimately unable to reconcile an inconvenient truth; The Force is a singular entity, and light and dark are each and aspect of it. The Force has a will, and it will always take steps to bring itself back into balance.
If either aspect of the Force is unrepresented, it will find a new servant with which to express it. This is why the Jedi and the Sith's attempts to destroy each other are always in vain. The Order of the Sith Lords has developed an obsession with trying to subvert the very thing they gain their strength from.
Darth Plagueis said that the Force "Must be broken" like "A beast of burden", and was ultimately led to doom his order because of this belief.
Kreia, from KOTOR II, in my view, has a much more comprehensive understanding of the Force, and the limitations of those who wield it. She considered the Jedi and the Sith to both be dangerous extremes with incomplete world views. Neither is able to perceive the Force because they are fixated on using it, and this is by no means exclusive to the Sith.
The Jedi, in their own way, have an equally skewed understanding of the Force. Instead of trying to dominate it, they evangelize it. They partake in the fundamentally contradictory task of trying to align their will with that of the Force, when it is the Force that dictates their will and destiny in the first place.
There is no emotion, there is peace.
There is no ignorance, there is knowledge.
There is no passion, there is serenity.
There is no chaos, there is harmony.
There is no death, there is the Force.
Each of these former examples is natural, and every bit a part of the Force as the latter. The Jedi code is fundamentally incomplete, and demands from those who follow it such a cloistered and joyless existence, that they practically guarantee that their members will turn to the Dark Side. A code that asks it's followers to ignore or violate the natural law of the universe will never satisfy the needs of every student of the Force. The schism between the two Orders is made inevitable by this code, not that of the Sith.
So thus, it is my assertion that the code of the Sith holds the true secret for living harmoniously with the Force. I will explain.
The key elements of the Sith code are freedom, passion, and the rejection of peace, but consider these ideals as compared to the actions of the typical Sith. Was Darth Vader truly following his passion when he executed children and assaulted his pregnant wife? Passion is simply defined as strong, uncontrollable emotion. Do love and empathy not enter into this equation? The Sith, perhaps in overcompensation for the faults of the Jedi, confound passion with it's exclusively violent and aggressive examples. Passion does not necessarily equal anger or hate.
Further more, describing Anakin's actions as inspired by something as trivial as hatred makes no sense. Hatred is simply intense ill will against someone or something; it does not presuppose unjust action if the subject of scorn is deserving of it. Anakin is not murderous or violent because he is capable of strong emotion, but rather because he misplaces them. He's not just "Passionate", he's hysterical and irrational; a trait that the Jedi's attempts to advise and direct him have only exasperated. Any psychiatrist worth their salt will tell you that you can't get rid of emotions by ignoring them.
Being passionate is a core point of the human experience; could you imagine going through life without ever feeling sadness or joy? Would such a life even be worth living? The affirmation of passion is absolutely essential to leading a satisfying life. Remember, it was not philosophy that ultimately lead the Jedi to victory, it was love. The base, simple instinct of a father protecting his son. Some of the most violent criminals in world history have been defined by a lack empathy; the very definition of a sociopath.
And yet the Sith deny themselves these things; they think only of themselves on principal regardless of what they actually want. This is an idiotic contradiction! And it flies in the face of their other core tenant; freedom.
How can one call oneself free, if one is prevented from pursuing their passion? What if one is overcome with a passionate need to feed the hungry, or driven by a deep love and affection for their friends and family?
The Sith code reject peace not on the basis of principal, but on the basis of objective, unbiased reasoning. Conflict is quite literally sewn into the fabric of life itself, and the pattern is everywhere. Planets are drawn to the orbit of their stars, and repel in kind; animals of all kinds survive by taking from the land and each other. The only constant, the only true stillness, is non-existence.
Harmony is not opposed to conflict, harmony IS conflict. The ecosystem of the Earth runs on conflict. Evolution runs on conflict. There will always be danger and strife, because these things feed the instinct to survive and thrive.
The Jedi fail to understand this, and the Sith misconceive of conflict as something that is generated by the individual, when in reality it is simply a function of entropy.
Total peace IS a lie, but it is not something that must be warded off or fought; it has never truly existed at all.
What I consider to be the true Sith, the perfected Sith, does not reject these things. He is defined by a Dionysian embrace of and affirmation for all that life has to offer. A sort of Nietzschian Ubermensch.
He is first and foremost true to himself, for good or for ill.
He does not fight the Jedi or seek to rule the galaxy out of dogma; his ambitions and passions are solely his own. If his passion should drive him to serve the will of another, so be it; if his passion should drive him to devote himself to protecting those he loves, so be it; if his passion should declare that he should hold the galaxy in his iron grasp, so be it; he cannot deny his nature, and he does not wish to
He does not destroy the obstetricals that oppose him because he believes himself inherently superior; he understands and accepts that all things are the will of the Force, and that he is no more objectively valuable than any other life form.
If he desires dominion over others, he recognizes this desire to be wholly of his own creation, and that the galaxy will not exalt him; he must earn and achieve power through diligence, willpower, and cunning. He accepts the responsibility of independence.
The Sith becomes totally accepting of the nature of existence, and truly one with The Force. The desire to subvert nature and impose his will upon the Force is gone, and the he becomes content with their lot in life; his chains are broken; the Force has set him free.
The Order of the Sith Lords in it's current form is every bit as aimless and futile as the Jedi, but it is in their teachings, their philosophy, that I see the true will of the Force.
"The greatest act of a warrior is to lay down his sword" - Hero