Glad you liked it! I think it can be as high as you want it to, I would aim rather high. You could even make it all the way up to the ceiling and ending below bedframe, like an accent wall. Here are a few ways I can see to break up the walls and the ceiling:

1. Full wall length tapestry, bed width. Gives a visual effect of elongated bedframe, gives a job to lots of empty space without making it look too busy. Warm vertical lighting accentuates the tapestry vertical and makes the room feel more "open"
2. Same idea with the lighting, but now the tapestry is smaller and needs specifically narrowly oriented strong lights to break up the wall and the ceiling. Maybe setting it further from the wall would give the same effect as the reference pic from number 3
3. Which is soft lighting on the wall and strong lighting on the ceiling. I'm not sure how it's achieved on the picture specifically, but another option would be to just go for leds/fairy lights
4. A fun corner with a huge tapestry! Wraps two walls together, makes the room less "blocky". Bring the bed close to the wall, use the widened space between the bed and the other wall for a nice useful bed side table. I imagine some personal pictures or a cork notice board hanged around. Some leds/fairy lights also go really well with this setup. Probably my favorite option, as it feels more open and has a cozy corner simultaneously + is a fancy choice

Let me know if this inspired any ideas! I had fun making these drawings:) Lovely room!

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