My guess is the answer to question 1 will be 20-30 years, in cargo aircraft. Then when they start crashing and scaring the public the answers to 2,3 and 4 will be never in anyone here's lifetime.
I do see advances in automation, next gen ATC system, more efficient routes, but the two person cockpit is here to stay for a while, being in a 141 program you should be thankful.