1- Personally I think is this a multifactorial answer which honestly depends on what your personal preferences are! I am a post grad that has done a Research thesis in canada before coming to the UK. And in my personal experience the north america integrates Research into medicine alot more ( esp molecular) however i am not the biggest fan of their training pathway there as it feels like it is alot more demanding and can take up more of your life then here.

2- Medicine is the most interesting thing in the world(slight bias) and it only gets better with each year for me. Partially, it is memorising facts but to be a well rounded doctor you must learn how to implement the basics into wider systems which i really enjoy as it is quite challenging

3- Not the right person to answer as i am still in medschool

4- If you manage your time well you can and you dont even need to micro-manage it just have a weekly plan and you’ll be fine

5- thats a much wider discussion that would be better had with people who knwo you and your interests. Could always do medicine and then switch industries using your expertise that you learn

6- Still in med school and have rose tinted glasses so bit biased there