It is not so simple. You could have some loss in performance if the page is too big. There is no universal solution just to make a 32K block simply because is "a regular banking database/application"... What is a "regular" anything in this domain???
So, let's get real! Nobody but you could take a corect decission! But we could recomend a way. So, start with 8K and test. You could be surprised to see the best results you will obtain with, let's say, 16K, and nobody here recommended you such a thing!!! ...