Wow, you seem to be very ignorant? De Boer has won 3 titles with Ajax in his first 3 seasons, knows our club and loves the philosophy of our club. To me the biggest pro for Frank de Boer is the fact is is very demanding of his players and staff. Just like Guardiola, Van Gaal etc are. You might not understand the language, but look at this moment:
After being 5-0 up against NEC, Ajax lost the ball due and let NEC score. Even though it's 5-0, there is still room for improvement. It reminds me of two people; Pep Guardiola and Carles Puyol. The latter fell out against Pique who wasn't concentrated in the last minutes of a 5-0 game or so.
Being very demanding can have it's toll, but I think that really is what is needed at our club. We don't want a puppet of Rosell/Zubi, but a critical and smart coach. De Boer is exactly that.