Question: I would find it more interesting/organized if there was a theme to follow for the featured images each week. For example, this week post only pictures of cars, flowers, landscape or whatever and change the theme every week.

Answer: 
If we ever did end up using a theme week, I'd like to suggest that we have a "un-edited" week, so the challenge would be to get the best photo out of your camera. Many of the photos seem to have a lot of post-processing. I'm not suggesting this is bad - the photos are stunning - but I bet there are a lot of excellent photographers out there who are not necessarily photo-editing gurus (or is that now a required skill to be a good photographer?).
Can I suggest a sports theme soon? I have not seen one yet, and have searched in the suggestiions.

I am fairly new to this site so do excuse if there has been a few already as I have searched but I do not want to manualy go through the archives of every week.