Ok to confirm,
1. I don't have the 'My Photo Stream' folder anymore because I turned the option to 'Upload to Photostream' option OFF.
2. I do, however, have a folder called 'Dino's Shared Photo Stream' which is the photos that I share with my designated users, using Photo Stream
3. The 'Camera Roll' folder is STILL there, however, in iOS8.1, it is now called 'All Photos' and NOT 'Camera Roll'
4. You are correct - the 'My Photo Stream' folder and iCloud Photo Library is basically the same thing so you don't need both - turn Photo Stream off!