I don't plan on reading "Zero Year" or any of its tie-ins, yet I didn't mind this "crossover." It helped set the relationship between Oliver and Diggle, and Lemire has done good enough job to overcome this obstacle of - what I believe is - a forced tie-in to the Batman crossover by editorial.
So I didn't mind this at all, nor did the fight sequences bother me. The low point really comes from the lettering, and I'm surprised the review didn't mention this. When an arrow (shot by Batman) hits Killer Moth's palm, Batman's word balloon comes from off-panel, and while the arrow was shot from the left, the balloon is on the other side of the panel. Same goes for a similar scene later, when GA shoots an arrow at Moth's wrist, but the panel preceding it shows Oliver's text coming from the other side. Otherwise, a stellar issue.
Did anyone notice the cool easter egg in the the backup story? Diggle reads a newspaper article about GA and who's signed on it? David Ramsey, as the actor portraying Diggle on "Arrow"!
I, too, had a problem with part of the book mentioned in the review, but it wasn't the coloring. The stars over Ollie's head really stood out and seemed too cartoonish for this kind of book. I assume it was added in post-production by the editors.
Otherwise, a very strong issue and the only ongoing series I read nowadays.