IMO it's important to try and impart mood and emotion to your work. After all we live in a world where most visual systems are inherently biased/limited so 'physically accurate' is a fuzzy goal at best. Personally I like to play with light, and that isnt easy with pure rendering. Much faster to just experiment in an image editor. It doesn't all have to be warm and bright of course, eg 'stark and inhospitable' could look like this: