Whatever you do with the brick (paint it, glaze it) make sure the product you're using is heat safe.

You can also update with a new gas fireplace, by choosing a unit with lighter media options, like driftwood or river rocks, your space will look brighter. Another option is to add faux birch logs to the wood storage for a brighter, cleaner look.

Oh my gosh, yeah, I would paint the brick for sure. That brick is very pink looking; not a favorite of mine and I love how fresh painted brick looks. You should also change out the brass for a new insert/door that is black.