Well, when a fanfic replicates major elements without adding much originality, that can be considered too similar. It might involve copying the overall story structure or not giving the characters any new development.
The 'a&k comic' is quite similar to its source. However, there could be slight variations in the plot development or the way certain events are depicted. But these differences don't take away from the overall enjoyment of the comic.
Overall, the 'This Hero for Real' manga is a decent adaptation. It retains the core characters and main events, but there might be some minor tweaks for artistic or narrative purposes. However, these don't significantly deviate from the essence.
The graphic novel of 'A Contract with God' is known for its strong connection to the source. It captures the essence and brings the story to life with vivid illustrations. Minor adjustments are made to make it more engaging for the graphic format, but the integrity of the source is maintained.