You are best off applying for several cards each and using the wedding expenses to easily cover the minimum spends. Barring that, get the Chase Sapphire or Fidelity Amex (2% cash back every purchase 0 annual fee).

But lets say you had $15k in expenses and got 3 card each with an average spend of $2500 and 50k points, you are netting 20% back if you conservatively value each point at .01.

For the 3 cards I'd suggest both Citi AA cards and the Chase Sapphire, might as well throw in the US Airways card too. If you have good credit and havent applied for cards recently you should both get approved for all 4. (apply same day)