What should I change?

I have 215 mil now (keep saving coins) what position should I change next? A CB or a midfielder? ( I want to change 41212 narrow) Only van de ven and casteel tradable

I have 215 mil now (keep saving coins) what position should I change next? A CB or a midfielder? ( I want to change 41212 narrow) Only van de ven and casteel tradable