I must preface this by saying that I haven't yet studied at INSEAD, but this is all based on discussions I've had with alumni and my own research.
1) The courses at INSEAD are intense but seem efficient, as the MBA covers the same number of hours as a two-year program.
I understand that mandatory courses aren't meant to go into too much depth, as they are very varied and you can choose to go into more depth with the subjects in later electives.
Many alumni say that every day is an experience with FOMO, as they have to balance work and many other activities and social events.
And there is time for many, many social events/parties and traveling!
+ you donโt need to stress too much about grades, because you are not allowed to share them with others nor will INSEAD disclose them.
Also you're definitely not alone, as many, many students have little or no finance and accounting experience.
This makes the first two periods harder, but INSEAD also offers an intensive business foundations course before the start of the program.
Considering that you have a lot of time until then you could try some online finance and accounting courses, but they are by no means necessary.
I would also recommend getting the two preparatory reading books (one of them is about accounting!).
The last three periods offer more flexibility and you can choose from all sorts of electives without having to worry about getting high marks.
I also recommend checking out the InTheKnow INSEAD student blogs to get more of a feel of the experience!
https://intheknow.insead.edu/blog/do-not-focus-academics-trust-me2) I could be wrong but I believe IESE may be better for pursuing banking in general in Europe, but INSEAD is the paragon of consulting and is very strong otherwise in many industries.
I don't know too much about IESE because although it's definitely a great school it's not as reputable or opens as many doors.
Also I'm not really sure about its brand strength in the Middle East/Asia but INSEAD's is very strong.
When I asked alumni from the business schools I applied to, I noticed that a very common thing people said about INSEAD was that it's a "life-changing experience."
I don't recall hearing that from other business schools' alumni.
Hope some of this helps! (and if you decide to go to INSEAD let me know!)