Is it a gas FP ? If so it really does not need a hearth so why not tale most of that away and just do a flat pieice of stone to fill that area and be level with the floor and remove the bricks and use the same stone for that area. A good sanding and painting of the surround and a new look for the FP

Yes it’s a gas fireplace

I'd replace all the tile and the wood surround, which is out of proportion anyway.

Honed black granite would be very simple and classic for around the firebox and the hearth. Since you don't have any more floor boards, you can get a slab of granite to fit in the space.

Depending on your style (Craftsman, Colonial, Modern, etc.) the wood surround could be just about anything. Perhaps identify what style you'd like so we can offer more solutions.

You may be able to get the same wood floorboards that can be feathered in and finished to match current floorboards.

I'd do a recessed/inlaid hearth with the same material you choose for the face/surround.

Can you post another picture showing what's above the fireplace and on each side?

All windows

Here are a few ideas for you:

Very simple mantel with dark stone surround and hearth.

Another view of same:

Very modern look:

More traditional but simpler and more in proportion than the one you currently have:

With a gas fireplace you don't need to have the hearth but perhaps you're no able to match the flooring so here are 2 ideas...

ou don't need an hearth with a gas fireplace.

It is gas but unfortunately we don’t have the flooring

@mikeanddeedp

My 1st picture just above shows an hearth that's the width of the fireplace.

Even if you don't need a hearth, it still looks nice and finished.