I always keep Sharpie, a normal, unevoved Porygon as a member of my team. I based it's move set off the one that Porycian (the Porygon from Pokemon Stadium) had.
It doesn't matter whether the battle is serious or not, there will always be a slot out there for that little guy in my party.
Also, some unevoved pokémon, such as Chancy, Pikachu, and Wynaut are not considered part of the NFE rank.