I would say it depends on what kind of data you are displaying, how much of it you need to actually have to display, and what you want the user to achieve with the data.
What is the desired call to action when displaying your lists? Is there any way to guess what data the user is looking for so that you can sort the list showing the most important data first.
For contacts: Do you need to display all available contact information all at once, or can you just display the contact name (or picture) and have more details appear when the user clicks or hovers over the contact? Can the contacts be sorted after how frequently the user communicates with a contact? Can the user choose multiple contacts and then do some action with them, and how would this work when the list is spread over multiple pages?
What is the desired call to action when displaying your lists? Is there any way to guess what data the user is looking for so that you can sort the list showing the most important data first.
For contacts: Do you need to display all available contact information all at once, or can you just display the contact name (or picture) and have more details appear when the user clicks or hovers over the contact? Can the contacts be sorted after how frequently the user communicates with a contact? Can the user choose multiple contacts and then do some action with them, and how would this work when the list is spread over multiple pages?