I had trouble initially getting into the first season of Arrow, but once I powered through an episode or two, it was fine. Season two was good too, but after that, it really started going downhill. Overall, The Flash is a better show, but it along with the others are marred by one major problem: they're a CW show. All of the CW shows seem to suffer from two problems that reek of daytime drama (soap operas): bloated casts and unnecessary/forced drama.
I stopped watching Arrow at some point, and I really hope The Flash gets better, because I wasn't all that enthused by this past season. I think it'll all hinge on how well they handle their heavily modified Flashpoint adaptation. Flashpoint was a story from the comics where The Flash (Barry Allen) went back in time to save his mom. Doing so resulted in a heavily altered future where the world was ravaged by a war between the Atlanteans (Aquaman) and the Amazonians (Wonder Woman), Barry Allen has no powers, Bruce Wayne died in the alley (Thomas is Batman, Martha is The Joker), and Superman is imprisoned. Obviously, they can't do all that as they have to usually scrap for any character rights they can get. (They finally got to use Superman on the Supergirl show instead of saying "my cousin".)