Palace need patience. They have made a statement of how they want to be run. Now they have to accept it takes time to change a whole club.
They have a good academy, and they dont have a bad squad (though "ok" is about as far as Id go!) and nobody expects anything more than surviving to be a success for them.
They need to give FDB time now to get his feet under the table, his ideas into the team and for things to gel a bit.
That said, as I said, FDB also needs to be pragmatic. Any idiot can see that Palace squad is not going to start playing like Ajax any time soon. He needs to settle on an interim system that works and gets results, and then build from there.
Maybe they go long, work on winning second balls, and then play on the deck more in the opponent half.
Maybe they sit deep and counter more.
Whatever it is, they need a shape they are safe in defensively that has some offensive ability.
Over time things get tweaked and changed, not all at once.