For the end game UMs, I used Shulk Dunban and 7th.
I used Melia / Shulk / 7th for the end game UMs.
Finally finished farming the cylinders I needed from them. Now I just have to get heart affinity with all my party members to see the remaining heart to hearts and I'll have completed everything one can do in a single play through (only things exclusive to each other like quests and certain colony 6 folks; will do a new game+ run to do those). Don't want the game to end, but I am very near to exhausting all the content there is.