INSEAD is consulting placement powerhouse. It is not a guarantee but their consulting club and training to a long way.
In the MBA space, a larger class is actually better. Having a small class is a disadvantage on many fronts unfortunately. Yes, you can explore lots of things but there are hardly any alums in your target industry. With INSEAD you get a much deeper network. The main advantage I can see in IMD is their older cohort if you are older; you won't have many or any 26 year olds and perhaps something you may need.
I would instead look at which program gets you closer to your job. I am not well versed in EU Banking or Investment options; I know in the US impact investing is super tough after MBA - too competitive.