This post contains spoilers for both Knights of the Fallen Empire and The Force Awakens.
I was playing Chapter 4 of KotFE on my Jedi Knight recently. This is my second playthrough of KotFE, and the one after I saw The Force Awakens. It struck me that there were some unintentional parallels between Chapter 4 and TFA.
In Chapter 4, your two main companions are Koth Vortena and Lana Beniko. Koth is a black man, who was a former officer in the enemy Empire's military. He deserted when he was ordered to massacre civilians. That's a fairly strong parallel with Finn. Lana, meanwhile, parallels Rey to a degree, being a powerful white female force user.
Of course, there are differences. The two are balanced better, Koth being the pilot and mechanic. Koth and Finn are both more classic good guys. Lana is a ruthless but pragmatic Sith Lord, the former Minister of Intelligence. To be honest, I think she's a far more interesting character than Rey.
One important difference is that the KotFE characters are both older. They've lived more, and done more, than the characters in TFA. That history makes them more interesting.
I was just struck by the unintentional parallel between the two stories at this point. Yet KotFE managed to do a better job with it's two characters, and manages to balance them better as well.
Of course, the biggest difference is HK-55. I'm pretty sure that an HK unit would have livened up TFA immeasurably.