This oneshot is honestly completely fine as it is, i feel like the crux of the work (which is essentially miscommunication), while cute in this short format, would get very annoying very soon if it was a full series. Characters talking past each other is like my number 1 pet peeve in romance stories.
That said I do hope that Ohsawa gets another full series running soon, it's been a while since Hello, Melanchoic ended~