Everyone seems to forget that Luke was taught lightsaber combat from an old man...a bad ass old man mind you, but an old man. Vader was half machine, his movements were clunky and his saber fighting choppy, no longer fluid like it was in his younger days. Luke defeats him in the same style, overhead two-handed chops, swinging wildly like he is wielding a baseball bat.
Guaranteed Kylo's training under Luke was based more on the force, the understanding, use, and theory.
They mentioned he disrupted the training Luke was doing and iirc he murdered several other padawans. Fast forward and now Kylo-Ren is the "apparent" apprentice of Snoke, his training not complete. Killing his father may be a final step toward completing his training.
As far as the final fight, I disagree that it was bad. I thought it perfectly encompassed where the characters are in their lives. Rey was taken from his family at birth and trained to become a stormtrooper. He is not a clone, he has free will...he's a soldier. He makes the decision that being a trooper is bullshit, and hatches the plan to get Poe to pilot a tie-fighter so he can get the hell out of there and run away to live a "normal" life. He has been trained in hand to hand combat and blaster rifle, but as you see in the movie he was NOT trained to be a pilot or a gunner, hence why he's terrible at shooting when in the tie-fighter and the falcon...and he also states it.
Rey is a mysterious character, clearly on purpose. Who are her parents? How did she get to be so stoic? Why did she act like she had witnessed nightmares before like when she touched Anakin/Lukes saber? Why did Luke look at her like he knew EXACTLY who she was? How did she know how to do the jedi mind trick, did she hear about it in a tale? It would make sense. All will be revealed in Ep 8 I'm sure, I have a strong feeling that movie is going to be 100% jedi/sith.
Kylo-Ren. Son of Han Solo and Leia Organa. Force sensitive. Trained from presumably a young age by his uncle Luke Skywalker himself. At some point he gets pulled in by the dark side, destroying everything Luke had built up to that point. His parents, crushed, separate for various reasons. Luke, as a jedi would, self exiles himself to go in search of the first Jedi temple to look for answers as to why he failed.
Now, in the saber fight, we know that Finn has melee combat training. We know that Kylo has also had training, from a jedi (and possibly a sith), and Rey is clearly no stranger to handing out an ass beating.
At this point, not only has Kylo been shot by a wookiee bowcaster in the side of his abdomen (a weapon that clearly blew the everloving shit out of stormtroopers earlier in the movie), but he also just murdered his own father. Not only is he severely injured, but he is in a state of emotional distress. His focus throughout the fight visibly wanes, and JJ did a great job of showing how Kylo was trying to regain his focus by beating his blaster wound to inflict pain on himself. At the start of the fight, he is toying with Finn. Once Finn shows that he isn't going to just roll over and die, Kylo appears to get anxious, finally striking him down.
So our bad guy sith apprentice, who still has thoughts of the light side trying to creep in, who wants to follow in the footsteps of his legendary grandfather, who resents the hell out of his own father that he just murdered in cold blood, who is severely injured, and who just for all intents and purposes killed a perfectly healthy lightsaber wielding stormtrooper, tries to force pull his grandfather and uncles lightsaber out of the snow.
In comes Rey. She is sad that her apparent hero just got murdered by this fucker, and she is angry that the same asshole just most likely killed the guy whose idea it was to come this this doom ship to save her. She knows the force is real, her hero told her so. She felt the force when Kylo attacked her mind. She confirmed her belief in the force by using her own strength to bridge the force-gap in their minds and read Kylos own fear.
She pulls the saber to her because she is ready to fight. She is ready to avenge her new fallen friends. She is ready to kick this son of a bitch right in the balls.
Kylo, being a sith apprentice, and also a young idiot, thinks that he can persuade her to the dark side because she would be a powerful ally. She attacks with fury, and probably some fear, and he attacks with pure rage and emotion, trying to impose his will on her (as a sith does).
They clash, she remembers what Maz said to her, and she lets the force flow through her. Fear was beginning to win, she was about to be pushed off of the ledge. It brings immediate peace, she is at one with herself in that moment. All of Kylo's rage and emotion that he was projecting toward her pass right by her. She has the focus now to deal the battle ending blow to him.
Now, in Episode 8, Kylo Ren is off to complete his training with Snoke.
Rey is off to (let's be real here, it'll happen) become a student of Luke Skywalker.
Now we will have two force adepts to fight each other in Ep 8 and 9.
I absolutely can't wait.