The main problem here is not the manga's structure, but people not getting said structure. If you go in with the assumption it will follow the "main pair" as the central driving plot you just misunderstand the point. Shiramine and Kurosawa are the framing device that holds the narrative together, but ultimately it is a story that follows relationships at the academy.
Unsurprisingly every person has their own story. And those you perceive as the "main pair" are also just parts of their lives from their perspective. So they will appear and influence them, but not be the actual focus of those arcs.
In return the main pair's relationship developed realisitcally over two school years and as any person knows, change doesn't happen instantly. We got the important stages inbetween the other stories as an overarching progress bar of the manga, but that's not a bad thing in itself.
Lastly for people who say they kept forgetting characters, that's more due to reading chapters over big stretches. Reading it in one go makes it pretty easy. It's the same issue as when people say something is a slow burn because they have to wait one week for every short chapter, but when they read 20 in a row it doesnt feel stretched out at all.
last edited at Mar 21, 2019 7:45AM