Finn, Poe and BB-8 made a fine trio; their scenes were easily the best part of the movie. It would be great to see them in the classic saga, perhaps during the Yuuzhan Vong War or its aftermath.
I feel like Finn had the most potential, but I don't feel like it was all that realized. For me they didn't do much with his character in RoS. Seeing a stormtrooper turn away like he was such a great start.
Finn had lots of character pontiall like storm trooper to rebel to hero to Jedi would be awesome. HE HAD THE LIGHTSABER IN THE TITLE PHOTO! He had so much potential. But we got a sand story again instead