I think a good start, unless you have already done this, would be to print off your floor plan and then cut paper rectangles that would represent the size of potential pieces of furniture you want to place in the room. (Or do the same online with PowerPoint or other software.) Where will the projector for the movies go, and a nightstand and lamp for the 'guest' part of the room? How many people do you anticipate watching movies in there at one time? Will they need tray tables for refreshments?

I agree with Glo. I’d do inside mount roller shades. They’re cute, easy to use, allow your pretty window trim to show, and can be budget friendly. If you google ‘diy roller shades’ ... ‘diy roller shades girls room’ ... ‘no sew roller shades’, etc, lots of tutorials come up. They’d be great because you could pick the exact fabric/covering you want. First one I saw: https://thediymommy.com/make-a-no-sew-fabric-covered-roller-shade/ ________ I like something like these, too (they can be embellished with cute trim, etc), but they might be pricier than you want, since you have four windows to do. https://www.blinds.com/p/bali-light-filtering-roller-shade/500969

I think I would make a design that has walls on the office as well. An office is not something that I consider a space that is pretty to look at and can get messy so having it in view of the public areas would bother me. The other part is what if you're on the phone do you want the noise from all the other areas to be transferring to your phone call? Say someone running the garbage disposal in the kitchen or TV noises from the living room, or just conversations, screaming children, barking dogs, etc. Not sure of your house make up, but there are plenty of sources of noise in a house. I work from home twice a week and having a place to go and close the door is very useful when others are around and especially when in meetings where I can have my phone on speaker and also work at the same time. This way I'm not disturbing others either and others can't hear what is being said either unless they stand outside the door and listen in of course.

Bump for the teen room layout ;) There are not many threads on this topic. Maybe post sketch with room dimensions?