I think that this room has a lot of potential!! The tones are all pretty warm right now, and you said your boyfriend likes cooler colors, so a good place to start would to be painting the cabinets and little nook above the bed with a fresh coat of white paint. Adding in new handles and hardware on the cabinets in a steel grey or silver could be a nice touch, too!
Then, I would focus on adding some new bedding in a grey, blue, or black. The nook could be an awesome place to hang some pictures or art that he likes, to bring some personal touches into the space!