I'm four episodes in and I love this series already. The reason is simple and the very definition of personal bias: this show seems to be an unending succession of miniature heist movies. I love heist movies. A team of characters following a plan that goes inevitably wrong: conspirators clashing, that one little detail no one anticipated, personal agendas getting in the way... I love that stuff.
All this and time travel as well. Okay, economy time travel at the moment but the production values on this series are so good you hardly notice that most of the team's destinations (so far) are the United States somewhere in the last forty years.
Actually, I was pleasantly surprised by how good the series was from a production standpoint. I always assumed a team like this was too expensive for network television. Of the nine main characters, four have pretty CGI-intensive power sets and another two have weapons achieved through special effects. They have a big CGI spaceship.
Speaking as someone who remembers when the best superhero team show was Mutant X (“best” is an intensely subjective term), I never thought we'd get something this good on TV. Its an impression reinforced by the fact that even the all-powerful Marvel Studios launched their TV offerings with a show based entirely on non-powered government agents and even now are doing solo series largely about characters with no powers or powers that don't require extensive special effects.
But, no, here we are with a show that will probably be a better team story than the Suicide Squad or Justice League movies. Which is fair since Supergirl is the best thing to be done with the Superman license since roughly 1980 and Arrow shows how much could be achieved by a Batman series that has the main character make some headway in dealing with his issues.
Between them Arrow, Flash, Supergirl and Legends Of Tomorrow are creating a shared universe to rival the MCU and, sadly, one that absolutely trounces the cinematic DCEU. That last part is less fortunate for DC but rather fortunate for me, a fan of the DC characters who is rather glad that there's some decent version of them in live action.