You are asking a wrong question. Keep both of your cards, at least until the AF hitsand apply for more, that's it. . If you're still flying Delta, the card gives you a free bag, and Cap One gives you 2X on every purchase.

When the AF hits, I would dump Cap One in favor of Barclays Arrival, which is slightly better IMHO. Certainly apply for Barclays US Air ASAP as the window is closing.