#1, remove tailgate before you hitch up. Leave it at home.
#2, Probably a good practice to lower the legs a bit. I do not really do this unless I have a leveling issue.
#5, I prefer to have some weight on the hitch. But yes remove most of the weight.
#6, I leave the rear stabilizers retracted until all is unhitched, level and done.
#7, chock the tires... this is #1 for me. But make sure you are level side to side first.
#10 & #11, I disconnect these before I pull the release lever.
#13, yea I want one of those. Ignore my leveling comments above.