Kylo Ren is the weakest Sith of the 5 main (listed) Sith Lords

Of all the Sith lords mentioned, Kylo Ren would clearly be the most powerful. Here's why: 1) Skywalker Blood When George Lucas first wrote the Star Wars saga, he made it clear that his original plan was to create a space fantasy epic centered on the destiny of the Skywalker family, and not specifically on the history of the Jedi or Sith at large (1). The result was that Anakin Skywalker was the literal Force Chosen One, and Luke Skywalker was the archetypical Jedi who would single-handedly defeat the Empire and bring peace to the galaxy. Of the Sith lords listed, Kylo Ren (with the exception of Vader) is the only one who can claim direct ancestry to the Skywalker family through his blood relationship to Leia. This gives Kylo Ren -aka Ben Solo- an indisputable advantage over any other dark side force user, he is the nephew and grandson to the two most important and powerful force characters ever created in the Star Wars universe (Luke and Anakin); and as a main character himself, he is meant to play a much more serious role in the future fate of the galaxy than either Dooku, Maul, or Sidious. 2) Strongest Dark Side Affiliation In George Lucas’ explanations of the Force, Jedi who followed the light side were meant to be warrior like monks who derived their powers from inner control of their emotions. Those who followed the dark side however, were intended to be the exact opposite. Sith followers are meant to be sufferers who give in freely to their impulses, their anger, their fear, and their hate. Emotional turmoil, in particular, gives dark side force users their force powers. Kylo Ren therefore is everything that a powerful Sith Lord should be. Unlike Vader, Sidious, Dooku, and Maul who are cold, chilling, methodological, and calculating in their emotions, Kylo Ren is anything but stable. He is fiery, angry, sick, and resentful, always acting out of spite and rage. Kylo Ren literally loses his marbles and wrecks entire rooms with his lightsaber whenever something goes abrupt, or lashes out at all those around him. Furthermoe his soul and inner being is uniquely locked in a titanic struggle to live up to Darth Vader's legacy whilst struggling to separate himself from any family ties he might have had as Ben Solo. The result is that Kylo Ren is the single most emotionally charged and motivated villain ever created for the Star Wars movies. And if the Dark Side of the force truly draws its power from emotions such as hate, anger, fear, pain, and most importantly, passion, then Kylo Ren's unique emotional motivations may make him one of the strongest and most gifted dark side force users ever. 3) Superior Galactic Influence Part of being considered powerful in the Star Wars universe is being able to influence galactic events (like Jabba the Hutt), and in this regard, Kylo Ren is certainly a contender for the top spot. Like Darth Vader, he is second in command to a fearsome galactic military junta, the First Order. Unlike Vader however, Kylo Ren is also master to the Knights of the Ren, a paramilitary group of assassins and dark side worshippers who take on explicit kill/capture missions from Kylo Ren himself. It doesn't hurt to mention either that the First Order has possesion of the Star Killer Base, a galactic superweapon more powerful than the Death Stars. Kylo Ren's unique leadership position in both these organizations therefore gives him unprecedented power to sway galactic events, where he is decidedly more important to the political fate of the galaxy than Maul, Dooku, Vader, and possibly Sidious. 4) Indomitable Will Of all the Sith Lord's mentioned, Kylo Ren has the strongest will and is least likely to cave to mental pressures. Unlike Vader, Kylo Ren had enough mental resolve in him to kill an immediate family member (Han Solo). He also had the stubbornness and resolve to shut out Luke from helping him while demonstrating unbelievable dark side fealty by killing his young padawans. Kylo Ren's mental strength of course, comes from him his lifelong obsession to outdo Darth Vader's legacy. This motivation in particular, gives Kylo Ren the mental fortitude and perserverance of an Olympic athlete who will stop at nothing at perfecting himself until his goals are ultimately realized. 5) Best Physical Conditioning Kylo Ren is the best conditioned fighter of all Sith Lords listed. The Emperor and Dooku themselves are old and past their primes. Sidious' body itself is ruined and scared by exposure to his own force lightning. Vader of course, is more mechanical and machine than man, and has trouble breathing and moving fast. Maul, while notably agile, has subjugated his body over the years to insane amounts of torture training and tattoo body piercings that deliberately keeps his body in a constant state pain. There can be no doubt then, that at just 30 years old, while having an athletic frame, Kylo Ren is the best conditioned fighter of the lot. 6) Best Lightsaber Weapon Kylo Ren's weapon is a specially designed lightsaber which feature a fearsome crossguard. The plus side of a crossguard is that Kylo Ren is better defended against the infamous saber slashes that cut off the hands of Dooku, Vader, Luke, and Mace Windu. Though a few saber enthusiast might argue that Maul has the best weapon, the advantage of a single hilt over a dual blade two-hander will always be that the non saber hand is free to use force powers. 7) Most Successful Star Wars Villain Of all the villains featured in Star Wars. Kylo Ren is arguably the only one to have bested all the main characters. He stopped Luke Skywalker's plans to return the Jedi to the galaxy by killing his padawans; he then demoralized Leia, Han, and Luke to the point that they each went on self-imposed 30 year exiles; and then to top if off, he helped revive the Galactic Empire in the form of the First Order, just when we had thought the Rebals had won in episode 6 and that the galactic civil war was over. 1)http://tinyurl.com...