What a nice list! The APA can help you with #3:

"Should you plan to pursue a career in psychology that includes practicing in the US, you must be aware that there are statutory and regulatory requirements for licensure in the different state and (Canadian) provincial jurisdictions, and you should try to determine in advance how your education and training outside the US will meet those requirements."

It depends on what State you will practice in when you come back: Frequently Asked Questions About Psychology in the US for Those from Abroad

I'm currently taking a course at Oxford and struggling with some of the same sorts of questions. The education given/background needed seems quite different to me.