Paint the end wall. That's actually a very modern look, quite popular right now. People are taking out attics all over the place for a higher ceiling/higher utility bill/less storage. Painting the ceiling and leaving the beams wood is also trendy at the moment.

You can paint it. I’d recommend a masonry paint. Romabio makes great paints for masonry. They’re non toxic, have a good warranty and easy to use.

Painting the fireplace will definitely modernize it. I painted a fireplace recently and think it turned out nicely. The fireplace is white and the walls are light grey. Was going to replace the fireplace screen but decided to clean it up really well and stripped off the brass inlays that were on it. Have never been a fan of tv above fireplace but have to say, it works quite well. I would suggest a rug in your room to anchor whatever furniture you decide upon. Would also suggest painting the wood trim in your room. Natural wood trim may make a comeback but for me it really dates a room. Good luck and please post after photos!

How much do you want to spend? or DIY? The carport is the overwhelming feature right now. Do you need it as a carport, or are you open to converting it to another use, like a sunroom or even just a covered porch? I think one thing that might work to reduce the impact of the carport but still keep it, is to remove the large filled in triangle below the carport roof, and replace it with a few horizontal wood beams, either stained or painted. Add some MCM looking wood trim around the doors and windows too, stained or painted to match. Add some stone looking cladding to match the house on the support columns. I think a color like the one on this house would look good -- with all the trim in either weathered wood, black, or cream as pictured