Fuck y'all, it's like no one has ever read drama-free Slice of Life before. Complaining about the pacing? It's fucking fine. Need more development from Hori and Miyamura? Why, they're fine too, they developed at a nice pace, with little to no development left for them at this point.
The only way the manga can go on right now without feeling redundant is mostly developing the side couples like it has been doing and having funny chapters in between, like it has also been doing. This is even more evident in the web series, where the ending (not far from where the manga is) is a time skip to the graduation and then a further time skip to when they're adults, and most of the material is actually from the Omake chapters.
There is no point in complaining, because this either ends soon in an abrupt way like the web series man story or simply ends later with more development for the side couples, and between these, the latter is a better choice as it'll actually have a conclusion for all the plot threads they've introduced.