1. We need the zip code field for credit cards;
2. We need option to add/remove custom fields;
3. We need option to show only selected fields.

Imagine we have an american credit card. It has zip code.

Let me add own custom field: zip.
I also want to add billing address field.

Let me choose what type of fields are: secure (hide information as a card number) or open (like notes).

Let me to choose what fields I want to see when open the card. I don't have any notes so I don't need an empty note field.

I want to show covered zip code and open billing address. I don't want to show pincode field coz it's empty and takes space. Also note field eats space but it's empty.

Also I don't want to show some custom fields but I want to have this information when I open to edit. Why? If I share the card I want to give only visible fields, not hidden