Need the plan/layout with dimensions to make any helpful suggestions

If you're really stuck you could make a small wall till the end of the cabinet, so the ceiling design doesn't fell awkward. I think this way it'll look the most in place, yet it will divide it more from the rest of the house. If you like it go for it...

The time to lay out a coffered ceiling was during design. It sounds like you are immovable on this, but realize it has nothing to do with being a kitchen. It has to do with the problems from what I see in the pic:

- Recessed, pendants, and ceiling register (probably not makeup air, but located over stove!) already installed: it will be a puzzle only a supercomputer could possibly computate - and still not solve - which is getting the lights to land in coffers, at an aesthetically pleasing location for it's own coffer and in relation to all the other coffers with lights.

- Corner pantry: angles always mess up the rhythm of the coffer polygonal layout and usually don't land perfectly within the coffer layout.

- Low ceiling: looks like 42" uppers with a crown under a 9' ceiling, so you have about 9" to fit in an 8"(?) coffer and your hand and tools to fasten and finish them over the cabinets, and then deep shadows above the cabinets if you could get it done. Otherwise, some scheme of closing in a soffit above the cabinets would need to happen.

- Island layout: you would probably want to center a coffer on the hood location. Which would make your island with it's pendants standout as misaligned, and if that is bar seating on the end would accentuate even more the un-relationship between the coffers and the entire cabinet layout.

- No consistent headers and offset wall enclosures (except with the Breakfast Area header): Your plan is open concept. The coffers will dictate visually the space below it. That space will not coincide with the space visually defined by the offset Mudroom(?) walls, the circulation space defined by the upstairs landing, the lack of header into the Great Room, and the small beverage(?) cabinet tucked over in the corner with a Great Room opening that won't coincide with the coffer layout.

So, the result of adding a coffered ceiling to the Kitchen will look very hokey, unplanned, DIY, and jerry-rigged. If you must coffer, maybe the Breakfast Area is a better candidate.

Your ceiling is too low for a coffers, and your home's aesthetic does not fit with coffers. As @3onthetree said, it will look wrong. I bet you could spend that money instead on many other things in your home.

The math does not work. If you wanted this, it should have been designed a year ago, during the design phase. Nothing aligns. You can’t just add it at the last minute when the math for the rooms is already set in wood and drywall, and electrical wire.

It would look totally goofy in a home with no cased openings with trim as well. The rooms bleed into each other too much. The entire style and trimwork of the home would have needed to change during the design phase, a year ago.

Everything @3onthetree and @M Miller said, plus…coffers are an expensive feature for grand settings, be them living rooms, dining rooms, or kitchens. Not to be snide, but your kitchen in far from grand. It’s a small kitchen, with very little cabinetry, and ceilings too low for a coffer.

Some years ago, during the design stage of a house we never built, our plan was for a coffered ceiling in a kitchen with 9’ ceilings. The kitchen was to be three times the size of yours, in a home that was planned to be 4,000sf. In a home and kitchen of that size, coffered ceilings make an appropriate statement.

To repeat what @3onthetree said, coffers are rarely successful as an afterthought. In your situation, the results will be less than pleasing.

Daughter and SIL have coffered ceiling they can’t wait to remove.
It was in the house when they bought it. It makes the ceiling seem so low and they don’t like the shadowing effects.