Actually what jumped into my head when you showed the bookcase and mentioned the shutter headboard is beadboard-textured paintable wallpaper - waybackwhen, many cabinets, including freestanding ones, had a beadboard back. It's less busy than patterned wallpaper or fabric (remember, it'll get busier when you get books in there, unless you go the covering-with-identical-blank-paper route) but it has more interest than an ordinary painted surface. Remember to paint the shelves the same color so they're not visually intrusive. However, most wallpaper dealers (brick and mortar type) have bins with "orphan" rolls of paper at a VERY steep discount. If you can find the time you might cruise through some stores to see what strikes your fancy.

I just finished a remodel and wallpapered behind my bed as well as in my bathrooms. I am absolutely delighted with the end result. I am not worried about wallpaper removal as I have no plans to remove it nor do I have plans to sell. All of my choices were driven by my personal aesthetics as well as my personal functionality - I am not worried about a mythical buyer in the foggy future. As to removal, I didn't put up the wallpaper nor would I be taking it down LOL. If for whatever reason I wanted to get rid of it, it would be done by someone I hired. FWIW, I remember my parents removing wallpaper as a child and it didn't seem that difficult. They used some kind of steamer so it was tedious but not highly skilled.

Thoughts: - That's a very neutral vanity, which will match pretty much anything -- that's good because you'll be able to change things up over the years. - That wallpaper is very cool! But it's a strong color. How big is your bathroom? If it's small or doesn't have a window, I'd consider using the wallpaper on an accent wall. - I don't love subways either -- too much grout and overdone. For the shower, I'd get a large-scale tile for the walls (either white or off-white, whichever matches that wall paper). I'd use a shower pan instead of tile on the shower floor. I prefer laminate flooring (warmer, easier on the joints), but if you're going with tile on the floor, I'd like to see penny rounds -- they'd echo the round jellyfish in the wallpaper, and they'd give you a pattern.

I think a wallpaper wall could work … can you show all angles of the room? Just curious how the rest of the house is decorated? What styles do you like? This came to mind for your room … I‘ve been wanting it myself: https://www.target.com/p/holli-zollinger-kalami-floral-wallpaper-mustard-deny-designs/-/A-83489407 Another beautiful paper: I took a quick look at your ideabooks and saw nice painted rooms, certainly that would work if you don’t find a wallpaper you like. In order: Benjamin Moore Kitty Gray: A stunning Morris paper, very pricey but so gorgeous! Couldn’t resist showing it. :D Another moody beauty: https://rebelwalls.com/vintage-flora-green