I suppose one way to think about it using the balloon/rising bread analogy is...
Think of the centre of the universe AS the big bang and the expansion being the time filling the "balloon". Or something.
Big bang go boom, time inflates space, pushing the skin of the universe where we live out.
I know it's wrong, but it stops all the "where's the centre of the universe" questions. The centre of the universe is the big bang.
Of course, using this model the universe looks a very weird shape indeed to residents of the "surface" cos light takes so long, so they pereive themselves to be on the "far away from the centre" skin, and then see the skin shrivel and shrink towards the centre as they look back in time.
I wonder if we'll ever be able to look back fat enough to see something CLOSE to the big bang. I know the microwave background radiation is that, but something as the first stars formed perhaps...