They needed to be a neutral color.
They needed to have an ankle strap so my ridiculously narrow feet wouldn't slide out while walking.
And they needed to have a wide heel. One, because they are so much more comfortable and easier to walk in, and two, because they look a lot cooler.
This is what I ended up getting, fitting all of my prerequisites to a T.
(photos collected from lolobu, womenfashiongalaxy, and by e.hunt)