It would be good to support network drives as a new source type.
Sequential transition should offer an option to remember where it left off in order to resume the slideshow on the next run.
It would be good to have an option under linked folders to include images under their subfolders.
It would be good to be able to set the image stretching mode in order to cover the whole screen when possible.
PhotoTV should be able to automatically detect the addition, deletion and modification of current images in a linked folder for all of the online sources (Dropbox, Google Drive and OneDrive) while in screensaver mode without having to restart the screensaver.
Add an option to the screensaver settings to display the date and time.