2) Supergirl
Supergirl has been great so far, and that makes The CW’s decision to pass on the series all the more infuriating. If they can come to a deal with CBS to make a crossover with Legends of Tomorrow a reality, then we’d no doubt be in store for a blockbuster episode (especially if Green Arrow and The Flash also appeared).
With no mention of Superman in their world, Kara obviously hails from an alternate reality, but that would make these heroes meeting no less satisfying. Simply put, Supergirl deserves the opportunity to interact with them, and using the team from Legends of Tomorrow to facilitate that would be clever and an awesome way to connect these worlds.
Ideally, that will then lead to crossovers with Arrow and The Flash somewhere down the line, but using Legends of Tomorrow to first increase interest in both this spinoff and the newly launched Supergirl would be a smart move on the parts of both networks.