I really hope Finn ends up being force sensitive. I think he will end up being so in the end. If he isn't I wonder why Maz showed such interest in him and gave him the light saber to fight with? She lives in a pirate castle! I am sure she would have had a more appropriate weapon for an ex storm trooper. Also the movie contradicts the books a little bit. Wasn't Finn the top of his class in the First Order? How the hel did he end up in sanitation?
She saw his feelings for Rey and knew he would deliver the lightsaber to her (which he did) which is what she wanted.
I'm curious to she how she came across the lightsaber after it fell into Bespin along with Luke's hand.