Telltale stated that they would release something to help tide us over until season 2 is released. If that something is a game, then I think Lily should be the main character.
Like her or hate her, Lily was a pretty interesting character with both assets and flaws to her personality, which make her complex, which make her easy to relate to. Even if you hated her actions, we all can understand where she was coming from when she did it. it would be a true shame for Telltale to let this character fall to the wayside when her story is practically begging to be told.
The interquel could began where Lily's story ended in season 1. This could lead to her being one of the two characters Clementine see's in the distance at the end of season 1.