Here’s a side photo! (We’ve just done flooring & trim isn’t up yet so that’s why there is a piece of quarter round hanging out)

Hmmm. If you did a wraparound mantel, I’m thinking whatever you do with the tile needs to wrap around that one side (Whether you paint or retile). If you want to paint the tile black, for example, I’d also paint the wall beneath it + the molding.

Hopefully a pro will chime in for you.

You don’t need quarter-round along the fireplace. The tile should reach the floor neatly. I would change the tile to a slightly darker gray stone and continue the it and a mantel around the side. Remove whatever requires the black electrical cord. The wider space on the right is perfect for a taller plant or a piece of sculpture or a tall urn.

Continue the stone...

I’m really liking the look of a wood mantel and continuing it around the side to create a little shelf on the side.

Felizlady, the cord is staying as our TV is mounted above the fireplace but I’m sure there are ways we could hide it a bit better just isn’t a priority at the moment. Manufacturer instruction as well as the installer advised that small gaps are a necessity to account for expansion (especially near the fireplace which gets quite warm). I would like to switch up what’s on the fireplace, I think a taller plant would be great on the right side and would hopefully help cover the electrical cord!

There are many versions of cord covers that you can paint the color of the wall. Use that to disguise the TV cord.

I would tile and wrap it around the corner and add a nice wood mantle (simple).

If your wall color isn't changing then I don't think grey tiles would look nice. Maybe there's a way to paint the firebox (heat-proof paint) so that it's not so stark.

All nice paint colors- black, white, grey, blue. Warm things up with a wood mantel

Loving navy and black these days 👌