Here's some key points from the novel, and for those wondering if Finn was well trained :
http://www.slashfilm.com/star-wars-the-force-awakens-novelization/2/
"At the beginning of the story, Finn is a cadet, not yet a full-fledged stormtrooper. We follow him as he progresses through his training and end with him preparing to go on his first official mission as a stormtrooper. We quickly discover that Finn, or FN-2187 (as he is called in the book) is an exceptional combatant and leader. Part of a four-man fireteam, he has naturally assumed the position of leadership on the squad. His team look up to him, and follow his orders, although they tend to distance themselves from him on a personal level."
So there you have it he was a very good soldier and a leader of men.
On Rey's piloting skills:
"When not scavenging or trading with Unkar at the Niima outpost, Rey spends virtually all of her free time building things and mastering her skills in flight simulations that she has restored from crashed ships scattered across Jakku’s landscape, which helps to explain how she knows so much about flying in the film and how she is able to single-handedly pilot the
Falcon with such skill."
And finally on Rey's parents:
"The biggest hints at Rey’s Skywalker lineage are from Kylo Ren’s perceptions of Rey. Just like the film, Kylo is noticeably shaken when, in addition to his inability to probe Rey’s mind as much as he would like, she can get inside of his. My, and many fans reading, will probably note another line of dialogue in the novelization that was absent from the film. It’s the moment when Kylo Ren calls Luke’s lightsaber to him and it flies right past him and into Rey’s hands. In the novelization, Kylo says to himself, “
It is
you”. To me, this says Kylo knew Rey or a direct descendant of Luke Skywalker was out there. Perhaps it was the one thing he kept from Snoke, whether that was Ben Solo keeping it from Snoke or Kylo, it seems Rey’s ability in the Force makes something CLICK in Kylo Ren’s head. Again, nothing solid, but much more brow raising when you read it in print. I won’t hypothesize the
why or
how Kylo may know, but I think this strongly suggests he does, and that is another reason the line was eventually cut from the film."