If you get the Platinum Delta card you will get 15,000 miles initially and another 10,000 at renewal if you spend over 25k in the first year. If you don't have big spending plans, go with the free card and the 10,000 Delta miles. Then just before the end of the 1st year, get the "Blue" card from AmEx. It has no fee, additional cards with no fee and it earns Membership Reward points which can be converted 1-1 for Delta Miles.