There are a few shows I’ve finished watching that were cancelled (Lie to Me, The Unit, OT, Army Wives) in which they have subplots that remain unresolved leaving those parts a cliffhanger never having a conclusion, even if they tried their best to provide closure that doesn’t come off as being rushed. For parts left unresolved, the only thing one can do is create fanfiction on assuming how it’ll end if the show itself is cancelled never to be rebooted.