Agree with @Betty Boo about the fireplace. You could have the faux stone rendered and plastered for a sleeker look. I like the colour of your paint but if you wanted a visual break try the darker colours in the Skimming Stone family like Elephant's Breath or Dove Tale. This will also highlight your books if you paint the built ins the darker colour.

It’s not faux bricks, they are real, my house is built with the same bricks.

I thought about have front wall only plastered but the plasterer said it will have gaps down the edges as the bricks are bumpy.

You could cover it with plasterboard first or render the front and side return to avoid the bumpy look. Would you consider painting them to make them visually receed? Painted brick/stone is quite attractive too.

I’ll have a think about that, thank you for your ideas.

What about Farrow & Ball Sulking Room Pink as an homage to the bricks? (I like the bricks btw.)