Just read an interesting article regarding The Force Awakens, which unfortunately isn't appropriate to share due to the frequent use coarse language. Nonetheless, the author does make a few good points.

This is in regard to the final lightsabre battle between Kylo Ren, Finn and Rey. One criticism that this scene has received was how Ren was "easily" beaten by two novices. Consider the following:
  • They were fighting a severely messed up Kylo Ren
    Chewbacca's bowcaster is significantly powered up in this film. Clearly Chewie has upgraded his weapon quite a bit during the intervening 30 years between Return of the Jedi and The Force Awakens. We see single shots from this weapon sending Stormtroopers flying some 6m through the air! This weapon deals some serious damage. After killing Han Solo, Chewbacca shoots Kylo Ren with his bowcaster and scores a hit. Kylo Ren takes a tumble, but he gets up and walks away, despite having been shot by a weapon that could flip a Jeep! Then, without any medical treatment, Ren goes out in the freezing cold and fights Rey and Finn. So really, Rey and Finn were fighting a severely wounded Kylo Ren. The guy needed to be in a Bacta tank, not in a lightsabre fight!

  • Finn and Rey aren't non-combatants. Okay, neither have been trained in lightsabre combat, but they aren't novices to melee combat either. Finn, legally known as FN-2187, is a professionally trained soldier. And we know that First Order Stormtroopers are also trained in melee combat, as demonstrated by the vibro-weapon wielding Stormtrooper who fights the lightsabre wielding Finn. Rey's teacher in the combat arts has been her life experience. Growing up on the hostile world of Jakku since a child and having to survive as a scavenger, Rey had to learn how to look after herself. So Rey basically developed her martial arts skills in the same way that martial arts were created in real life in the ancient world and in the same way that evolution works -- she didn't get killed! (re: survival of the fittest) If Rey wasn't a naturally talented survivor, she probably would've died in childhood. She didn't have adoptive parents or an uncle and aunt to raise her. We see her successfully fighting off multiple opponents in hand-to-hand combat. Finn ran to her rescue, but by the time he got there the rescue wasn't needed. Then Rey chased him and beat him down. Han Solo even acknowledge that she can fight. Mix in her heightened Force sensitivity, and you have one naturally potent fighter (Luke and Leia on the other hand were raised in environments that never allowed them to develop melee fighting skills; Luke as a farmer, Leia as a statesman).

If you take the world's best boxer or martial arts fighter, shoot him in the stomach with a high power rifle, then put him in a cage fight with a person who's had Army training and another person who grew up in a violent slum in a third world country, then yeah, the odds of that "ultimate fighter" being able to win the fight suddenly goes down.

P.S.: There is still another criticism of that fight which I must admit that I find ridiculous and cannot justify, and that is a really long pause where Rey closes her eyes and begins meditating before defeating Ren. Really. As if Ren is just going to idly stand there while she summons the power of the Force to beat him. Sure, Vader did a lot of this when he fought Luke in The Empire Strikes Back, but that was because he was toying with Luke. It was never his intention to kill Luke, he wanted to recruit his son. Ren has no such objective! The dude had just killed his own father, there's no apparent reason as to why he wouldn't kill Rey. And even if there were, he could still easily have beaten her without killing her, like chopping off her legs or something. She was just standing there with her eyes closed! (gah... this is why I can't stand to watch martial arts competitions...)