Will the entire room be circular? I can’t really tell from this angle, but if you do, it makes most sense to fill all sides of the walls with bookshelves and to possibly save the centerfront for three curved windows such as the one below, except ground level.
Or another wall design you can take inspo from is the Library of Congress
Ofc, these are assuming if your layout will be circular. Good luck!
Adding to a circular room, you could create a really cool and detailed chapel like thing. Maybe even adding a telescope or something in that genre with a fireplace and a desk? I’d recommend to add some layers as in floors with small ladders and cosy spaces with these chairs