The broadest theme of "The Force Awakens" is that which awakens, which is the light side of the Force. Let's talk about this terrifying concept a little.
We all know from decades of being immersed in a culture with Star Wars videogames, Star Wars merchandise, and Star Wars Expanded Universe books, and Star Wars related media (like the TFA trailer) that there is a Light Side and a Dark Side of the Force. So it's easy to forget that nowhere in the movies before TFA does someone say "light side".
In the OT, Luke never wins a lightsaber duel. (Except against himself.)
In the movies, the Dark Side is a distorting power, and there only exists it and that which is outside of it. Of course, this concept in our culture becomes another thing to be labelled, measured, and eventually merchandised. The fact that every Star Wars videogame needs "light side force powers" is exactly what was being parodied in "midichlorians".
Whereas the depiction of the light in The Force Awakens is quite interestingly different.
For one, we are repeatedly shown examples of black, crenelated orbs. We get the fighters chasing Finn, the Super Death Star, and the wrathtars captured by Han. These are our visual image for the Dark Side.
And these orbs are annihilated by a searing burst of light. Light comes in like a rey (pardon the pun) and just destroys it.
This leads to another weird tick of TFA. You know what else was never mentioned in previous Star Wars movies? Light speed. What little we know of their space travel is based on jumps to hyperspace (a form of travel that changes your perspective more than about your locomotion.) One should not get lost in trying to explain the physics of a metaphorical universe, but it's obvious this is a significant change.
TFA mentions light speed twice. Are these instances of describing the characters in terms of momentum and velocity?
Oh right, light speed is a weapon.
Specifically, they ram through the aforementioned rathtar by accelerating to light speed, obliterating that dark orb. And then, light speed allows them to get in under the shield and sabotage the Super Death Star.
This depiction of light as a searing, powerful weapon as new. And in the very same movie, we have a character that agonizes about being seduced by the light. It's an active force Kylo Ren must resist. Audiences of course hope for Kylo Ren to choose the light, but it's another thing for the light to impose it's will on anyone. It's a great deal more evil for the light to destroy and compel.
In TFA, the new Jedi wins her lightsaber duels.