It does not have to be symmetrical. The mock up looks good. I do not like a TV above a fireplace so you can even do shelves on the right side only and none on the left to put your TV on instead.

I suspect AI fudged the proportions and if you tried to reproduce the look, you'd find the right smaller and the left larger than shown in your mock-up. You notice the left back corners and the fireplaces on both pics more or less line up, but the right corners don't. In short, you can't use this mock-up to show you what it will look like if you try to reproduce this, unless you also move your right wall out a foot or two.

I'd put built-in on the left and a tree on the right.

Do a tall cabinet to the left that is the size difference width between the two sides. Then the base cabinets can be the same. It should be slightly deeper, to create a better illusion of symmetry. But the whole installation wasn't really designed for built ins, as the fireplace projection is way to shallow for that. You could just fake it, with a bunch of cabinet doors, and then hang art, but I suspect you want storage. Which will only make the recessed fireplace look darn awkward.

Here's a similar example of an uneven fireplace wall. I think shelving and cabinets would fit nicely within the bumped out fireplace surround.

Even if it were a symmetrically placed fireplace, what would you do about the fireplace being flat against the wall? The built ins will project forward of the fireplace.

Do you want built-ins because you need more storage? What kinds of objects do you need to store and what is their depth?

Do you use the fireplace, if not would you cover over it?

AI rendering does not show what you actually have in the room. Do you plan on moving the whole fireplace box about 22" forward?

Builtins for what purpose ? I think the 2 low cabinets to match in style but different sizes with the TV wall mounted on the above the left cabinet and a piece of art above the right one is what I would do . Adding shelves to hols stuff not needing dispaly is silly . If you have stuff you need to display then share that with us so we can help with shelves .The inspo you posted is exactly what you have BTW but all I see ther eis a bunch of stuff picked up at winners to fill the shelves which IMO is silly

Just playing - superimposed the AI version over your picture, splitting it into 3 sections that match your original picture.

AI is great, but it still has limitations and may make impractical improvements (like moving the fireplace over.

Thank you all for the comments! The main reason for the built ins is just to enhance the space and add some storage. It’s just feeling drab and I figured built ins would just level bit up. I didn’t consider that the fireplace is flush to the wall and that would look weird with the built ins.

@jennifer hogan thank you for the image, that was super helpful!

You could make your life easier by not having to completely revise the wall and fireplace.

These ladder bookcases are from CB2

You could definitely do built-ins on either side of the fireplace. They don't have to both be the same size. You could do shelves on one side with a cabinet under it, a bookshelf on the other, or even leave the other side blank and put a chair there with a floor lamp and side table. Below are a few visuals to help you more.

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