Using the vertial and horizontal axis extending from the centers of objects, as well as the page itself, would be extreamly helpful. Right now there is the align tool that can align to center, but that moves all the objects involved to the median center, which does not provided the desired solution.

This would also include the center axis of the object being moved.

If you've never used it, I would encourage you to test out Apple's KeyNote to get an idea of how quick it is to line items up on center using it's snap implementation.

This would be most useful in Impress, Draw and Writer.