YOu can change any pictures or group of pictures you want. Use photo stream. You can show folders for all pictures you have taken yourself. Or you can collect as may as you want that you want to save or add. You can keep them as albums. Individuals pictures. Or on Photo Stream. You can do exactly what you want. You just need to sit down and work with it a little and understand the features. Click on the Sunflower icon in the bottom Dock to get started. I hope that helps. I think that is what you mean, anyway. Hope so. Also you can download iPhoto from the app store and use that. Very close to the Photos in the Dock.
Also, once you have loaded tons of photos into the iPad...i notice that when you start at the slider window to open the iPad there is an icon for Photos there.
If you click on it....even before you slide the slider, alll the photos will be presented in fantastically organized and interesting inserts and folds and stuff. Very very cool. But you need to actually have uploaded some pictures into the iPad to get that feature going.