If the brick is a functioning chimney I would leave it other wise a rough render could work. One of the issues is that the nearby features such as the light and painting clash. As in the dining room, try a large mirror and a big photo e.g. to link it all. Also good rugs with strong reds, browns, oranges would help co-ordinate the rooms at low expense. I would try a colourful Moroccon style rug near the brick feature before attempting a major fix.

I realized i forgot to update what i did with the wall.. Now I know so many people said not to go ahead with it, but i am pig headed and did it anyway. It took me 5 days (about 15 hours to fill in the mortar and then 2 hours to put on 2 coats of paint. I am really happy with how it turned out. I understand it is not quite 'industrial' but i was probably lacking the correct terminology for what i was after (in truth i wasn't sure what i was after, it was more about not wanting the wall to stay in it's current state!)

Dr Retro House Calls, funny as I have a sample of monument here. Interesting about true black. Girlguides I have also been playing around the idea of ironstone on the garage doors. Attic Building Design you're right, the picture doesn't quite show it, they are mission brown, thinking of a grey/black. It's such a huge decision, hubby and I can only agree with no cream or green.

Hard to see the brick clearly on your photo, but it looks like plain colour brick without different colours through it, and no textured finish. So in this example you have a completely different coloured stone and a non patterned brick, which does look okay. But if your brick has various colours and you have a coloured stone wall then it is way too much and the texture and colours compete against each other. This is only my opinion.