Hi,
I think you have to sort of ignore the speakers, from a design point of view. Even though they are big black objects, so is your TV. They are there for a reason. I think you need to focus on what you'd like for the floor, sofa, curtains, media unit and wall colour. The floor, walls and sofa are the largest surfaces in your room.
I would personally prefer a wooden and/or white media unit, wood (effect) floor, medium to light coloured sofa and medium/light coloured walls. You could consider painting the TV wall in a darker colour, so the TV and speakers won't stand out too much.
For example: I know these speakers are smaller, but it would also work with your larger ones. It's everything but the speakers that makes this a cosy room. If you know what I mean :-)
Q
mix of colours
Q