I think Arrow is a victim of its own success. Because of how well the first two seasons were received, more shows were made. Instead of all the focus by Berlanti, Kreisberg and co being put into Arrow, it was spread amongst other shows. More focus has been put into Flash, LOT and Supergirl than Arrow the last few years, to get them off and running and to get them a stable and loyal fan-base like Arrow has. If Flash and the others never happened, and all the focus was put into Arrow like it was in the first two seasons, it is unlikely the drop in quality would have happened IMO. It is a shame for me, as while I like Flash, I prefer Arrow at its best, and I would have chosen for Arrow to have stayed season 1-2 quality rather than have the Flash made if I had the choice. It sucks, as I am a big fan of Ra's al Ghul and the LOA, and they would have been better if all the focus was still on Arrow. Season 3 really could have been epic IMO.