I would think the solutions depend on your budget laddie 903. For a less expensive solution, I would leave your brick fireplace as is. Beef up your shelves with trim so they look more substantial . Remove the glass tiles completely. They really date the room. If it were me, I would then add to the shelves on both sides of the fireplace by building up to the ceiling, leaving a nice area in between for putting in a piece of art, or mirror , if that's your preference., If it was a mirror you could then add some colourful vases etc, whatever works to tie in to the rest of the room. But definitely beef up those shelves

I second the idea of eliminating the open shelving and perhaps replacing with closed cabinets. Therefore, I like the first photo @Theresa Janssen posted very much; the second one not so much (but only because there’s a fine line between tasteful and tacky when working with wallpaper).

Oh, and removing the mirrors, of course. ;)

There is some awesome peel and stick wallpaper out there, you could put right over that mirror and not have to take it out. Then you could put a mirror back over the fireplace leaned against the wall But I might opt for a pretty piece of art. Beefing up the shelves with trim would be the best bet for the built-ins.

I will see what can be done with molding to improve the bookshelves. I'm not sure how difficult it will be to remove those stick on mirrors, but will check on that also. I didn't realize there might be stick on wallpaper to just cover them up.

The walls will be painted a warm off white color, not yet selected, and I'm wondering if the bookcases/mantle should be painted the same color as the walls to blend in, or white for a contrast. What about the fireplace brick color?

Right now, with the exception of the white bricks, everything else, including ceiling, is painted the same color Glidden Antique White. I'm looking for a slightly deeper off white color this time though. I'm finding some of my samples, of various brands, have appeared too yellow on the walls so far.

I would use a brick veneer to continue the fireplace above the mantle, painted to match. Then paint the walls above the mantle and the backs of the shelving below in a deeper color to add some interest to the wall. You could use artwork or a framed mirror on the brick above the mantle.

It all depends on budget - IMO the mirrored tiles should be removed as they really date the space. The painted brick fireplace is pretty and on trend so I'd spend your budget in other areas. While I usually love bookcases on either side of a fireplace, I think the size and configuration of these are not working cohesively with the fireplace. There are too many cubbies and shelves and they are too high to look appealing. I would probably remove them and place two chairs on each side of the fireplace and replace the mantle with something more appealing.