Each of these makes a huge difference not only in knowing each individual donor but also knowing your donors as groups. If your donors who read science and history magazines are more likely to retain, that needs to be accounted for in your modeling. But you’ll never know that unless you know who reads what magazines.
And you’ll have additional ways to get in touch with your donors. Every donor has a phone, a mailbox, and an inbox with their own strengths: email is inexpensive, telemarketing can be personal, and mail tells compelling stories. You need to know each way to get in touch with your donors and if they are likely to be responsive.