I finally caught up on Arrow. Pretty neat season 3 arc. I've not been acquainted with Ra's al Ghul outside of Arkham City and Christopher Nolan's Batman. His actions here seem consistent with how he's portrayed in those stories.
The problem with watching season 3 now is that I already watched the Flash while it was airing. This made the crossovers a little wonky. Whilst watching Flash, I caught the Arrow cameos, but I couldn't really see the big picture. And then when binge-watching Arrow several months after having watched Flash, I had to try to remember where the story was between those two. Also, now the beginning of the Flash makes more sense to me when he travels to Starling City to confide in Oliver about his newfound hero status. Not having watched Arrow first, I wasn't even aware that Flash was really a spin-off.
And if I had not watched the Flash, I would not have known that Black Canary had some gear modified by Cisco to be more effective in crimefighting. Also, I got some spoilers on Black Canary. Whilst binge-watching, it was like one day Black Canary just suddenly gained sonic abilities.
When the new seasons of the Flash and Arrow come on board, I need to make sure I watch them concomitantly. This is not how I normally watch television shows, so it'll be a little change. Then there's like the quasi-Avengers/Justice League show based on these characters, which I'm actually looking forward to.