Should I retake the GMAT?

ok, so, no it doesn't look bad to retake it multiple times (unless you have taken it like 6 times and don't improve)
I took it 2 times so far, scored a 670 on my first and a 700 on my second.
besides. the only issue ofcourse is that the GMAT isn't cheap (approx $300 each time).

as long as you improve between attempts, it's shouldn't have a negative connotation.
also, you can chose to cancel your score and nothing will be sent out to the Schools.
that's my mindset going into the 3rd attempt now: if i have a better score, submit it, if i have an equal or worse score, cancel it.

how heavily each school weighs each portion depends on the school, but you can probably find out more on the schools websites about that (under their FAQ section most likely)

i know IESE only looks at the total score, ignoring AWA and IR, but further in the admissions process they might look at those.
all in all, your GMAT score is depending on your situation. for me, I didn't have that great a GPA, due to studying a new course at Uni which hadn't been "calibrated" yet. so my 13/20, was above average but still, doesn't look like a good GPA. The GMAT allowed me to demonstrate that i'm not a 65% student but at the very least at 88 percentile student.

final advise: if you feel you can improve, it's worth retaking. You have time to study and prep for it.

Thanks for the detailed reply. I guess it's something I should consider holistically, since my undergrad GPA is quite high maybe this isn't such a big deal. Or at least not a total deal-breaker.

I do still have quite a bit of time before applications are due, so I guess I might as well...

Yep! You might as well. Especially since you can cancel scores...