Both Mosh and I are luke-warmer skeptics (if I can speak for him). He is an author on some of the BEST papers under review right now. I am a physical scientist.
1 through 3 are true. 3 is based on “simple” physics.
4. This is the real question although I think 10C is a stretch. All the unknowns about clouds, cosmic radiation, water vapor, and other feedbacks will determine how much the planet warms and how much is due to GH gases.