What's the rest of the room look like? Want to make sure suggestions are in line with your style.

I vote for the whitewash and a new screen! Not a pro, just my two cents! :-)

This is looking the opposite way from the fireplace. The blue dog bed's no longer there. The door opens directly into the backyard. Ignore the kitchen; I've completely remodeled it.

Oh, and as for my style, I'm pretty eclectic, but tending toward modern. Our furniture has fairly clean lines as does my new kitchen.

You can go over the brick with tile or add a wood fireplace front. Here are some photos of fireplace front I have design and had done for my clients. The first photo was almost identical to your fireplace to begin with.

You can also go over the brick above the mantel with drywall like you said. It would need to be built out with 2x4 to allow the drywall to apply. Please note that this will add thickness and may become wider than what you would like after it is completed. You could add a wider wood mantel to help but might need something on the lower half to have it look in proportion with the top.

Here is a BEFORE & AFTER PHOTO. We removed the rock and added drywall. Check with local building codes to see if these can be done in your area. Wood stove almost always require a tile or stone hearth 24" out of the floor. This project we went with a gas insert and had it high enough off floor top pass local codes.

Here are a couple of drawing ideas, along with another fireplace front I did that lean on the contemporary side. Each of these tile ideas could be done over the brick.

I like that slate look. Very pretty. I don't know if I'd go with that much decoration (you can see, we really use our mantelpiece for displaying photos) so keeping it simple would be great.

Paint out the brass with high heat paint. Then, the most immediate thing you can do that will have the biggest impact is restyle your mantel with photos in the proper scale.

Mix tall and short, b&w and color, frame everything in simple frames, keep the whole arrangement within the confines of the mantel. Have some larger pieces--16 x 20 or so--in back.

Plain slate 12x12 tiles are not that expensive. Keeping it simple would look good. You could tile the bottom section with a darker slate and above the mantel with a lighter colored slate that complements it or wrap it in wood veneer to match the mantel.

You may not realize it, but you have what a lot of people want. You just need to update a bit. A quick paint job will modernize your look dramatically. Whitewashing or painting the brick charcoal grey would add instant glamour and modernize it. Beef up the mantlepiece (replace it with reclaimed distressed wood or something substantial or paint it black to save $$ so that you can put some beautiful accessorries on there). The mantle as it is now looks weak and dated. This is a gorgeous focal point - let it shine - make it bold!!!
Add a round mirror with a gold metallic frame or artwork on the top part (don't forget to accessorize with beautiful things). Move the TV to another part of the room -it's too distracting and competing with your lovely fireplace. Remember, you need some bling somewhere - the room looks dark and dated - mercury vases - candlestick holders, etc. Please don't do slate...........sorry...........that's so dated. Start with paint and see how your like it. Love the family photos. Try doing a photo wall on another wall and that way you can keep adding and editing your collection. Cramming them on the mantle is not showing the photos well and is hiding your gem of a fireplace. Above all, enjoy it.

Yeah, the TV is a problem, but there's no good place for it. It's not a very large room. I have lots of wall space; I'm planning to paint before I commit to hanging everything. My initial thoughts are having the fireplace wall a bold color with the other walls/ceiling a warm neutral.