First, I would say don't cancel your mastercard. If you've had that card for 10+ years it will help keep the average age of your accounts higher which is good for your credit score. The card isn't hurting you at all by keeping it.

A card to apply for right now would be the Continental Mastercard. There is a 50k bonus right now and there is a large thread somewhere around here about it. CO doesn't fly to your home airport, but you can redeem their miles for travel on US.