I feel they could have had an amazing story arc for black Canary taking atleast five seasons to complete. (This will only go over black Canary story arc) In the first season it could stay similar where Laurel is an alcoholic like her father. And her sister is the current black Canary. Captain Lance dies by Cheshire mid season for trauma on Laurel. Laurel then goes further into abusing herself. Loses her job. Tommy Oliver and family are the only ones really trying to help. Season one finale Tommy dies. Season 2. Laurel is pretty broken and in the dumps. Sara or (felicity) convinced her to go to AA and group counseling where she meets wildcat. Wildcat helps her emotionally while he hides his vigilante side. Season two mid season he could start to train her. Oliver finds out and isn't happy she went to someone else (especially because they're so similar) and confronts wildcat. They have a mini brawl (for the fans) and discuss Laurels emotionally state. Ending in wildcat helping Oliver get his vigilante shit together since wildcat was part of the JSA. Season 3. Laurel is becoming a more proficient fighter and feels better about herself. She even gets her job back as a lawyer. Wildcat is a reoccurring character. Mid season finale Sara dies by Huntress (history with wildcat [huntress could have killed Tomcat to justify him not being apart of the series]) to spark her real motivation and fire inside. Laurel trains her ass off until the point where she drops Oliver a few times (black Canary is supposed to be as good of a fighter as most DC heroes). Season 3 finale Laurel finds huntress and dawns the black Canary outfit for the first time. She has huntress dead to rights but decided to put her in jail instead of killing her (because she won't let that darkness consume her). Season 4 Laurel is depressed and conflicted on what to do with her life. Does she always want to fight crime in both her real job and vigilantism? The next story arc is pretty much from Justice league Unlimited. Laurel notices wildcat isn't around as much so she investigates and discovers he's doing under ground fights with villains, street thugs, and anyone in the ring to fill his need for justice and he isn't too rich so he needs money. Mid season she confronts him but he says he will continue. Black Canary gets her Canary cry during cross over with cisco. If you've seen JLU then you know the finale but this time Thea (or felicity if you want to see her destroyed) and Black Canary fight each other and it's up to wildcat to make the moral choice. End of episode wildcat moves and is gone as a series reoccurring character. Oliver thanks him for the mentoring and support with laurel. Laurel pretty much thinks of him as a father so the good bye would be touching. Season 5 is about the doomsters and the begining of black Canary and green arrow romance. I don't know a ton about the doomsters (from a foreign planet that became polluted so they altered with it allowing them to thrive on pollutants) arc but it was the first comic showing the spark between the two (precrisis). The finale would have to be the cross over episode so it would be the ' CW Justice League' taking on the doomsters. It ends with Oliver freeing up enough time for others to defeat them.

Let me know what you think or if you may have enjoyed it. I enjoyed just thinking of her imaginary story arc.

Edit: I feel it is just as important to build the character that make Green Arrow as it is to tell his story too. I would have done Roy's story arc much different too.