first thing I'd do is remove that white mantle! it doesn't coordinate well and the white just sticks out.
I'd do a solid wood mantle, something like this,,,, (this was for someone else, so ignore the paint colors)
See this mantle? like this
then you need to lose all of the tiny little items on the mantle and decorate w/something like this. a taller piece of art, one or two vases, knick knacks.
or, something like this one. (this stone was white washed)
do you like that brick color? if you dont, you can white wash it, mortar wash it, or paint it whatever you like
this one has a curvend mantle because it's more rounded than yours.
photoshopped this one onto your pic.
Q
perfect
Q