Love this color scheme. Thinking about doing more of a charcoal grey as the base color and then just throwing in some coral throw pillows and some white ruffled pillows to give the room some texture. I would switch yellow for the coral.
I hate the word upcycled, and probably wouldn't go for the pink, but this chair is pretty cute, except for the leg tearing studs, which are hideous and stupid. Upcycled Dalston chair dip dye studs - Die lijkt me nou leuk op mn hobbykamer!
With its adjustable shelves, the IKEA Mandal headboard is already fairly adaptable, but have you thought of using it in ways other than a headboard? These folks did; perhaps it will inspire you to look at the Mandal with new eyes of possibility.