I'm gonna have to disagree. The Flash has had some of the greatest comic book moments I've ever read. If there was ever a JL character to deserve his own movie (other than Supes or Batman), its Flash. The dude has an awesome rogues gallery and so many untapped and awesome stories.
Yeah, but he can also phase through walls, create whirlwinds, run through time, run between dimensions, steal peoples speed rendering them immobile, gives him a healing factor, (etc...). The Flash is the one character with super speed that somehow translates it to a plethora of other super powers. Barry, Wally, and Bart are so much more than just a power set too. They're all unique, fleshed out characters (Bart is my personal favorite speedster, though Barry and Wally are also awesome).
Plus, we have yet to have a legitimate fight scene in super speed. Could you imagine him and Zoom going at it with a proper budget/special effects? Quicksilver running into some robots and getting shot just doesn't compare. The only real proper super speed scene made so far was Quicksilvers in Xmen, and many consider that the best part of the movie. That pales in comparison to possible scenes with the Flash.
You say super speed has been done to death (Wolverine, on the other hand, we can somehow watch stab people for 10 movies), but I think people have barely scratched the surface. Writers usually stay away from characters with super speed because they are hard to write for.
There was a pilot made for an aquaman tv show, with the guy who played green arrow on Smallville playing the lead. It was awful. I'm just waiting for some kind of animated or live action version of the character to be shown using telepathy on things other then fish, since a version of Aquaman from the comics could straight up mind screw you.
__________________ But we all got a Chicken-Duck-Woman thing waiting for us.
I remember tuning in for its premier and being super excited way back when. The theme song for the title was also done by my all time favorite band, not to mention I was the exact group they were marketing to (age wise) at the time. I thought it looked awesome, and was genuinely disappointed it wasn't going to continue.
Then they brought back the dude who played aquaman as GA and it fit him perfectly, so I got over it. He ended up being one of the best parts of Smallville and I still, to this day, believe he's a better Green Arrow than Amell from Arrow