Hi there,
I wouldn't take van Gaal, although he must have learned his lesson at Barcelona. He is not a globetrotter. And he made lot's of mistakes at Barcelona on the social level, like buffing up top players in group sessions - normal in dutch culture- but something Spanish players really don't like, and Rijkaard & Ten Cate make sure they don't make the same mistakes. Also he is not so good with the Press. I would ask Johan Cruif who to sellect next. He is the real genius, why do you think Rijkaard got a change at Barca in the first place ? But I agree that van Gaal is a top coach, his old assistent is doing good in Chelsea too.
Beenhakker is very well adapted after the many years he stayed in Mexico, he is also experienced and that is what you need. But there are good coaches all over the world, good thing with the dutch is that entire level of football coaches is very high therefor all the assistents are also quite good, it is very important that the entire team is top. ( Keepertrainer, scouts etc)
my 2 cents