I was very interested in watching this, as I am a big fan of the original manga, and was curious on how they'll adapt a story that had 3 volumes when the show first aired. My guess was that they would either stretch the plot out or expand the story, and they went with the ladder, which can sometimes lead to the adaptation straying too much from the source material, or in this case, risking the possibility to include any future material in sequel seasons.
While I haven't watched the second season yet, the first one managed to blend the original pieces and side stories wonderfully with the main plot, expanding the overall universe and characters in a way that doesn't ruin the story, but makes the fans of the manga feel like they received bunus content (if that makes sense).
What also helped the show keep that "Minato Shoji" feeling was the main cast's ability to perfectly portray our lead characters, as well as the editing and music that kept the summer nonchalant, slow life type of vibes.
Can't wait to watch season 2!!!