I didn't expect a Yuri hater would show up here.
well, I guess there is place for everyone be it harem hater, gay hater or both.
anyway. they look lovely together.
Story wise, Amane and Miharu living alone is still unresolved case. As far as I know there not much drama beside that.
Tho living "alone" is another questionable point as they pretty much living together.
I believe the term are there because once upon a time (like a Millennia or more ago) they are "real" witch. they do divination, potion making, physician, record keeping etc. well you can see them as "smart" women that the royalty keep as advisor.
the novel are pretty much just like this.
the school arc are just that a background for all the main character to connect and gather,
if the title say anything about the story, this story still in character introduction part.