COASTROAD Hearth & Patio Most fireplace shops (like us) have a wide variety of "off-the-shelf" AND semi-custom designs available. There are many designs that are are available in a variety of wood species and stain finishes and custom sizes to fit your needs, like the J.C. Huffman mantel below, which is similar in design to the shelf shown above (the stone appears to be European Castlestone by Cultured Stone).
In my experience, a stone fireplace that goes all the way to the ceiling is not overwhelming, but rather provides a welcome anchor for the room. In the photo above, the ratio of the relatively small fireplace opening to the width of the stone wall (perhaps 10-11' wide) is unsettling for me personally, but "different strokes", as they say.

Stopping the masonry short of the full ceiling height can look awkward.
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REGINA KURTZ Thank you for your compliment on the fireplace design. The mantle was custom made by the same people that did all of the cabinetry around the fireplace and it was designed in conjunction with the cabinetry. The actual mantle is between 6" and 7" tall and approximately 6 1/2 feet long. Not being able to see your room, but judging from the dimensions that you provided, I don't think such a scale would be overpowering.