Looking at most big boards and mock drafts, it looks like picks 13 - 17 are going to be loaded in the secondary: Joe Haden, Earl Thomas, Kyle Wilson, Taylor Mays.
If Joe Haden is still there at #13, he is far and away the best player available -- mock drafts are starting to make jokes about how quickly the 49ers will turn their card in for Haden (unless Trent Williams is there).
So say we take Haden there...why not take Kyle Wilson, Earl Thomas, or Taylor Mays at 17???
I think Earl Thomas is the next Ed Reed, and Kyle Wilson is simply an amazing punt returner and looks like a star in the secondary as well. Mays has the highest ceiling in the world, but I don't know if he will pan out.
So, we may be best off taking TWO DBs. Optimally, Kyle Wilson should be one of them because he fills the returner need.
Haden/Thomas, Thomas/Wilson, Haden/Wilson.
Thomas/Wilson would fill the most needs (safety, CB, KR/PR).