That said, why the HELL are they green lighting so many damn Batman projects...
They have plans to activate any IP they can, the main advantage of more projects is not everything has to be a tent-pole, event, fate-of-the-universe film... letting off some of the pressure and giving you fall-backs if things fall through.
Basically, I'm guessing the WB is looking at their light 2018 and wishing they had been more aggressive in pursuing small bets to snatch up some of that Deadpool money.
More movies means smaller films can fill in those kinds of gaps and normalize expectations so that the massive event films don't get taken for granted when compared to the lower budget bets.
So far each DC film has been carrying the weight of the entire franchise on their shoulders with some in the audience getting upset that not every movie is a life-changing, history-making event. I think the "success" of
Suicide Squad is making them think they don't necessarily need to be so precious about every film. That's good in that we're going to get more films, that's bad in that they probably won't do risky high-concept stuff like BvS as much (if at all).
That might make them more experimental in the smaller films though.