Q: "Any feedback on our tiny guest room?"
A: We are asked often how to make a guest room look better, how to plan for one, what color should a guest room be?
I think a guest room foremost should feel comfortable, cozy and welcoming! Great start so far! A few suggestions that I have for you:
Orient the bed along the wall that currently has artwork (rotate the bed 90 degrees) This will allow you to add a headboard which would be more comfortable for a guest sitting up in bed.
You can purchase bed bases with or without headboards. I have included a photo of the simple bed frame from west elm. It comes with a separate headboard that you can purchase.
I have also had custom headboards made by local upholsterers. Upholsterers carry a wide range of fabrics to choose from based on your budget and aesthetic. It is often cleated on the back so that it can be mounted to the wall at your desired height depending on the height of your bed base/mattress.
You could include artwork above the headboard depending on the overall height of your headboard. Its nice to have an accent color throughout a given space. In this case the existing blue throw on your bed could be used as the accent color and you could select your art based on that accent color. See the reference print I included. I have purchased prints from many online shops, in this case the one I included is from Society 6. you can order to fit an existing frame you have or order one from Ikea or other frame supplier.