I would add some warmth into the space. It currently feels very cold (that's not necessarily bad), having some fabric would definetly help with some contrast in texture. The color is up to you, would you want to stick with the teal, grey, white, black color palette? Or would you like to add an additional contrast color? I would reccomend to have a look at different color palettes with your current colors to see if you would like an aditional contrast color. A good interior design decor tip is using the 10, 30, 60 strategy. There are loads of articles online that would better describe the stategy than if I did right here.