Personally I think those items would just bulk up the code where not really needed. Take the logo for instance, it is something you only change once in most cases. To do that is often just a matter of replacing an image. However, sometimes you may wish to resize its container then a couple of css adjustments are needed. While it would be possible to add code for both it would also mean that theme developers would need to be quite strict in many areas of their theme development so from my POV it would not be the best of ideas. If you look at most CMS packages their template designers often take the same view.
As for anycontent, surely if a developer is knowledgeable enough to create such code they also have the skills to upload a file via ftp and set its permissions?