[Matrixbeast]

I think taking their time would've been the smartest move for DC, anyway.
Not just in terms of quality, but just, well...Timing.
If they released their solo hero flicks during the tail end of Marvel's big Avengers finale, they'd basically be a breath of fresh air.
No more cluttered films juggling 10 heroes. It'd be 1 hero, 1 villain, and only glimpses of something more. While Marvel is working new cameos in for every new hero, audiences who want something simpler would get that by having just Superman, just Batman, just Wonder Woman, etc etc.
By making all their films big multi-hero flicks, they're basically turning themselves into "Avengers but darker" for every movie.

One could argue that DC didn't want to risk the super hero film bubble bursting by waiting for Marvel to finish first, at the rate DC is going, they risk bursting that bubble just by how they make their movies...