I was looking at some mind-boggling $ lighting when we built. The designer said to buy what I loved and just put builder grade stuff everywhere else. That is food for thought. But what I found once I had a glass of wine or two and started looking online was that there is really wonderful lighting available that doesn't cost a body part. Also found a lighting store in a nearby city that has a huge sale every August. Got some great stuff there.

Bamboo roller blinds are an inexpensive fix. They can be cut to fit and have a decorative look.

I would do gray walls and just make sure it has the same undertone as the tile I often paint the ceiling the same as the walls if going with a light color or if a little darker for walls I cut wall color 50% for the ceiling. I have a gray and mostly white LR and I have walls a color called Vancouver Day from C2 I then add color for different times of the year with pillows and a few accessories The wall behind the sofas I just painted in a purple from one of the pieces of art and I love it.

I love dark shades but from my experience oil stains on a dark shaded cabinets in kitchen specifically are more prominent.