I can see the consternation: in general, movies, with greater budgets, actors, and simplified storytelling, can hit a higher mark then most TV episodes. However, a good TV show can hit that mark a few more times if done right, thanks to seasonal story progressions, slower pacing, and the sheer number of times they get to try something.
For instance, the entire emotional tension and strife of Slade vs Ollie plays better in the show because we had an entire season of episodes featuring Slade as the heroic mentor and brother-in-arms before he became the antagonist. And while the flaws in his turn are apparent, the show carried the transition thanks to Manu Bennett getting loads more screen time to show his tragedy than he would have in a movie. Anakin Skywalker had a better reason for going to the dark side, but Slade's execution of the turn was better.
Similarly, the show has the grace of being able to reinvent and redefine a failed character translation instead of being stuck with a poor variation of a fan-favorite character. Deathstroke and Vertigo have both received new actors and new directions, Thea was pulled from the fan loathing by better writing, and Deadshot was upgraded to a more badass character design and personality after a lackluster first appearance. Even Laurel had some redemption for her code name done by Sara, and since she has so many episodes left to grow, she can get out of the stupid as well. In contrast, DC's DVD continuity is now stuck with a poser as Deathstroke until at least the next two movies, and the Mandarin (who can kind of be compared to the Count on Arrow) is only slowly unravelling the misstep made with his character.
But I've always argued for separate universes for one primary reason; TV can focus on the side characters and benchwarmers who have great potential, but perhaps not immediate marketability. And that's Arrow's checkmate to Agents of Shield, and it's a strength shared by Gotham.