Sorry forgot images

Murphy bed?

How do you want to use the room as a library? Will you want a desk for an individual? Maybe in front of the double window? Or instead a round table for reading/writing at and maybe games? An easy chair with lamp and side table for quiet reading? As a guest room, will you need a chest for storage? End tables and lamps for the guests to use as bedside lights? Think about function first, and then the how. Especially in a smaller room, having things do double duty will be essential.

Going off Annie's comment, here's a post with some ideas on combining library with guest room.

[https://www.houzz.com/magazine/double-duty-design-the-library-and-guest-room-stsetivw-vs~73070831[(https://www.houzz.com/magazine/double-duty-design-the-library-and-guest-room-stsetivw-vs~73070831)

One thing to determine -- and if you already know, to let us know here -- is whether library means simply bookcases/book storage, or if a desk is somehow involved. And how much storage do you want for guests? How big is the closet? Is that enough for a guest?

Also, while your style choice is different, when I heard library/guest room I immediately thought of Natasha Habermann's recent One Room Challenge. It could easily be adapted, especially along the lines of the Copenhagen apartment, for Scandi modern industrial style,

https://www.natashahabermann.com/single-post/2017/11/16/ONE-ROOM-CHALLENGE-WEEK-7-THE-REVEAL

@Annie - Thanks for the consideration. It'll be a room to store books & read. I'm considering a comfortable airy reading chair facing the window. No desk required & no extra storage needed (we already have half empty closets in the house).

@Becky, thanks for the suggestion & links! I hadn't considered a floating futon/convertable sofa! What a neat idea.

I definitely agree the lighting needs to change. I've been considering a cable lighting kit to replace the fan so that there are multiple light sources. Ceiling is 8' & husband is 6'6" though so I don't want something right in his face.

Older family members may not be comfortable on a futon bed. I find them awful to sleep on. How about something like this for your long wall, a TV bookcase left of the closet and a second bookcase opposite the window?

@decoenthusiaste - Thanks for the suggestion! I've been researching organic latex/wool/cotton futons that seem like they would be superior quality because comfort is certainly a concern. I'm also open to similar sofa beds, they just tend to be quite pricey.

The ones pictured above are more like daybeds. The support under the mattress is a concern too. Here's another version. The cornering headboard with pillows against it gives support for sitting up, lounging and reading.