My first save was with them this year, so I have a few suggestions.
I wanted to develop their youth players so I introduced Van de Beek, De Ligt, Noa Lang and Che Nunnely to the first team in the first season. Letting them play cup games and sometimes be on the bench, and also being tutored if possible. But let them be available for the Jong Ajax or U-19 team so they also get regular game time.
Formation: 4-2-3-1, Control, Fluid, take advantage of wing play and the overlapping full backs.
Cillesen
Van Rhijn/Tete(FB, Attack) - Veltman(BPD, Defend) - Riedewald(Improe his strength)(BPD, Defend) - Boilesen(FB, Attack)
Schöne(AP, Support) - Bazoer(BWM, Defend)
Al Ghazi(Winger, Attack) - Klaassen(Shadow Striker) - Fischer(IF, Support) / Sinkgraven(Advanced playmaker/Winger, depending on the opposition)
Milik(Complete forward, attack)
Can upload screenshots of any players, formation or transfers if you want. - Went unbeaten in the league in 2. season.
Edit: Forgot about Justin Kluivert, he is also a very decent prospect and should also be given a chance. Try and improve his pace would be my suggetion