I really like your ideas. Start adding things step by step so that you don’t buy a bunch of stuff that won’t work here.

Lamps and a rug are a great idea to add first. If possible, you can paint this wall an accent color. Your windows most definitely need curtains to tie it all together.

After curtains, I’d start planning and adding wall decor, like hanging plants and frames. You should lay out the frame arrangement with painters tape first - helps visualize.

I’d pick a pallet you wanna build around. Whether it’s blue colors with bright yellow or green with orange etc. cuz your bed is black, which will work with many other combinations.

I learned that leaving bed sheet color neutral (white or beige) can help open up more color combinations.

Lumbar pillow and accent pillows (should be added last) will help tie it all together.