The contrast between the heroes and the villain in "Justice League of America" #57 makes for an interesting dynamic. As the Justice League regroup and plan to take on Eclipso on the moon, the villain advances his schemes in a big way by setting his eyes on his successor as the Vengeance of God, the Spectre. The heroes regrouping and strategizing gives the issue a down, transitory feeling that's balanced out by Eclipso taking on the Spectre. Conceptually, it works quite well. The execution is where the issue falters.
The biggest problem is Brett Booth's art. When he draws a clear picture, his art can look good. He has a dynamic style and is adept at drawing the more lanky, toned characters rather than the over-the-top muscled ones. Except, he doesn't often draw clear pictures, preferring cluttered layouts that don't do his line work any services. Looking at one of his pages, the eye doesn't know where to go first and it simply slides off the page. These are compositions and layouts that repel rather than engage and draw in. Add to that, the quality of his line work fluctuates greatly depending on the panel. Some panels have a nice command of detail, while others look like nothing more than rough sketches.
The layouts of the pages aren't helped by James Robinson overwhelming them with words. It's not a matter of making the issue a 'denser read,' it's that so much of what's on the page seems superfluous. It's endless droning on and on without getting to the point until a page later. The dialogue in the Justice League's scenes in particular drags the comic down as Robinson has them purposefully talk around their plan, so there's a clear indication that they have one, but it's rarely directly discussed. And, yet, they still fill page after page with discussion about it. It's a lot of talking about nothing.
The Eclipso scenes suffer in the same way, but, there, it matches his personality. He obviously likes to hear himself talk and couldn't shut up even if he wanted to. What he says also matters. If you cut his dialogue, you would lose important details and that's not the case for the Justice League. His showdown with the Spectre is handled well and feels like a big, important fight -- one that actually sets up a rather surprising cliffhanger.
From a plot and structure standpoint, "Justice League of America" #57 is solid. The Justice League regroups while Eclipso advances his plans to destroy Earth, giving off a sense that everyone is screwed while balancing the two halves of the issue well. The execution falls down with cluttered pages that seem to do everything they can to make the reader lose interest and look away. There's potential here, but it's not reached.