Hopefully clearing off the mantle by putting the cable boxes on one shelf

We have seen some customers put wood veneer over their existing mantles, that could be a nice option for you.

Tone down the shiny ceiling and install track lights instead of the builder's boob light. They can be focused on the shelves which should be styled with 1/3 books, 1/3 large decor and 1/3 open space. No photos in the shelves please. You have pictures on the TV to watch. Paint the shiplap, mantel and cabinetry all the same white.

Im sorry but I don't get why anybody would whitewash brick it never looks right. Why not just go all the way and pain the brick there are plenty of dark trendy colors in a gloss finish that would look great.

You can still stain the mantle. If you paint the mantle a tan color you can then use a gel stain on top of it and it will look like wood. Stick with darker to med tone stains. General Finishes makes great stains and Old Masters actually sells the tan undercoat which they sell for front doors.

Home Depot has low cost large format tiles that you could use on the hearth.

Thanks for your suggestions! The wall of the bookshelf is hale navy, it just photographs really darker than it is. The lights don't really bother me, I actually have recessed spot lighting right in front of the fireplace too. I agree on the books, and pillows- really good suggestion! The insert is actually brand new, it's kind of a pewter grayish, but I'm wishing I went with black. And those corvel holes will be plugged for sure! I'm quite happy with the white wash too! Much better than it was!

I like the idea of paint the ceiling a flat white and the area behind the TV the same Hale Navy as your book cases. I think getting the mantle to a dark wood tone as another commenter posted will go a long way to improve the whole look. Add some attractive colorful artwork and boxes on the shelves and you're all set. It will look so much better! Have fun.

Paint ....err, replace the carpet. By making your brick gray, now your beigey greigy carpet looks icky pink in contrast.

If your colors are gray, navy and white (as youve stated) then a black fireplace is not going to fit in, in any kind of meaningful way. I think you need to go about this more wholistically - come up with an actual color scheme for the room and part of that is seeing how it relates to your other rooms and furnishings. Otherwise its just kinda hit or miss guessing what should be done next.