Wedding Favors - Postcards

I've been trying to come up with a cute idea for favors for my cousin's wedding. My criteria was something cute, personal, and cheap. Somehow I stumbled across the idea of postcards.

I have some experience with graphic design so I figured I could handle designing these. I researched places to print them. I really love the quality of prints from www.mpix.com, so that was the first place I checked. I researched a few others but I think mpix is the way to go. 

It's still a work in progress and waiting on my cousin's feedback and approval. But this is what I've come up with so far. She's using a damask pattern in her ribbon and a few other details of her wedding so I decided to incorporate it.

Front: 
(we will replace the current picture with one of their engagement photos)

Back:

There's still a lot of work to do. I need to find a way to include their names or a catchy phrase on the front part. The letter to the guests will change, it'll be something written by them. But I like the progress and the overall concept of this favor.