You should pay off your existing credit cards, but do not close the accounts. If you do, that good credit history will be removed from your credit report, and that will result in a lower credit score and probably a lower credit limit. With your current credit score you can apply for credit cards with mileage rewards. These cards allow you to earn miles for every dollar you spend. Some also have a 0% introductory APR. Also, some of the cards do not charge an annual fee.
Disclaimer: This editorial content is not provided or commissioned by the credit card issuer(s). Opinions expressed here are the author's alone, not those of the credit card issuer(s), and have not been reviewed, approved or otherwise endorsed by the credit card issuer(s). Reasonable efforts are made to present accurate information, however all information is presented without warranty. Consult a card's issuing bank for the terms & conditions.
All rates and fees, and other terms and conditions of the products mentioned in this article/post are actual as of the last update date but are subject to change. See the current products' Terms & Conditions on the issuing banks' websites.