Bigger samples, whether it’s paint, carpet or upholstery are always better to see colors. Also, picking paint last is the best option. It seems like a big yellow space with gray carpet. Ask the carpet place if they have larger samples you can bring home. Either order Samplize samples or paint on a large piece of foam board that you can hold vertically to the carpet sample to see how they work together (same orientation as walls vs. carpet). Look at it next to the brick also. None of those carpet colors on the left seem right to me.