So just updated to iOS 9 on my iPad Air 2 and almost all the iOS 8 wallpapers have vanished??!
I had a wallpaper which showed the Earth at an angle, with a blue haze around it - but that's now vanished?! Is this the same for everyone or just me?!!
If you are willing to spend 3 bucks, Pimp Your Screen is available in iTunes. IMO, it's worth it. The screens are absolutely amazing and it includes HD screens. New screens are updated frequently.