Tile is hard to choose. Paint not quite as bad. Still, there are lots of choices.
I’m going with the Benjamin Moore “Affinity Colors” which allegedly can be mixed and matched arbitrarily. Here I’m trying out a few options. Home Depot will mix 8 oz. jars of paint from the Benjamin Moore fan deck chips for about $3 per jar. So, I had a bunch of colors made and tried them out. I knew this, but forgot: don’t test really subtle differences; they don’t matter much, and are so subtle it isn’t clear the small swatches would tell you much. Just test the really distinct alternatives. However, you should definitely test. In my case, I decided that these reds were just too red. I’m not going to use them. I’m using variants on the khaki and two shades of the “pumpkin.”