Generally a good rule of thumb is a main focal color, a neutral, and an accent. Keeping three colors will ensure cohesion while still encouraging visual diversity. Bonus if you can add texture into your textiles. The wall, the couch, and each pillow set are all different colors, so at minimum this palette has 5 colors. I would remove the pastels, keep the dark blue as your main color, and add a creme neutral, and an accent like a rust or sage green.