It’s visual height/weight needs to be balanced, so consider the overall effect.

There are .many options for an overmantel that don't include stone/tile. As shown above, shiplap is one option. There are really pretty mouldings that people have used over there mantels - I have a lot of examples, I'll find them and come back in a bit!

Are you picturing something like this:

Take a photo straight on, not tilted up to the ceiling so we can create some concepts for you.

For starters I'd select a linear fireplace so the TV screen is mounted lower.

The higher you move the fireplace, the higher the TV screen.

If you'd like for me to make a few images showing different ideas, you'll need to take a better photo - you need to move further back + take the photo straight in front of the wall. The current photo is over the the side and angled.

The one thing that I would do no matte what type of overmantel you decide to do is to build out the fireplace a bit from the wall. When fireplaces are placed flat against a wall, they look odd. It makes a huge difference to just have it extend out from the wall just a bit. If you'd like to add cabinets/shelves on the sides of your fireplace, you'll need to determine the depth for the fireplace so that the built-in shelves or freestanding pieces don't stick out into the room more than the fireplace.

Here is an example of a really awkward looking fireplace - tile was placed flat against the wall + there is no mantel:

If you use moulding, you don't have to cover the entire front with wood panels - you can simply build a bump out with drywall + add wood trim pieces - and then use trim paint over all of it. The flat drywall will look like it's wood because it will match the moulding that has been added.

All of the below overmantels can be extended for taller ceilings.

You'll notice in some of the examples I've included (like the next one) that the fireplaces have been only slightly built out from the wall - that works also (unless you're adding built-ins next to the sides of the fireplace).

This fireplace below would have looked odd if it would have been the same depth as the overmantel - the surround was "built out" in order to work with the custom built-ins added on the sides of the fireplace:

I've seen examples posted that have combustible materials too close to the opening of the firebox. There are different clearance requirements based upon the type of installed firebox.

The below fireplace + overmantel is pretty - however, using stained white oak is more expensive vs. drywall + moulding/trim + paint:

The below fireplace was an inspiration photo for the fireplace constructed by a DIYer:

Initially, she made the overmantel out of drywall and painted it with an accent color:

She later decided to add the trim pieces:

The DIYer added simple shelves on each side of the fireplace - they are easy to add (even for a novice DIYer).

If you post a photo of the entire wall + show the rest of the room, people will be able to propose specific ideas for your room that work with your decor style.

Have the frame designed to go to the ceiling to replicate a true chimney. Drywall added, and make the two windows work into your design.

Yes that is beautiful but my ceiling is 18 ft+ so not sure we can do it.

Thank you so much for the help

I don't usually object to a tv being mounted above a fireplace but your tv would be well above window head height if you install a conventional fireplace and mantle. That might be too high for comfortable viewing.

Yes, we are trying to figure it out. Thank you