The hard part is thinking up what you can do for your customers, with the database, that the customers find valuable to them. If you can't think up a good answer to that question, your database project will fail, and you should not waste money on it. Your goal, therefore, is to come up with a great idea for building a customer relationship that will be valued and appreciated by the customers, and will be cost effective for you. Since everyone else today is thinking up similar programs, you will have to work hard to make yours stand out. One way is to discriminate between your best customers, your next best customers, and your average or poor customers.
Discrimination is essential.
If you treat all customers alike, you won't be able to afford to give very valuable benefits. I suggest that you use RFM analysis to separate your customers into quintiles. The top quintile are your best customers. You want to devote your service dollars to this group. Give them royal treatment.