James Lafferty would've been a much better choice for Bruce Wayne over Benjamin Bratt/Simon Baker. The guy was supposed to be around the same age as Ollie/Lex wasn't he? The "actor" seems like he's on par with the likes of how Conroy's Batman in Batman TAS looks which is a Batman operating for at least several years longer.
I loved One Tree Hill as well and it would've been fantastic to see Lafferty "back on TV". I was more or less expecting a Batman/Bruce Wayne similar to how he was depicted in the other Batman animated series "The Batman", who was much younger.
Kate Mara does seem like an ok choice for Barbra, how about Holland Roden?, age wise she's on par with the likes of Conner Kent/Lucas Garbriel as well as Kyle Gallner/Bart Allen.