May I ask why you are moving the cooktop? It seems it currently sits between two windows which is actually a very current set up. Cooktops on the island are never a good idea, and were done back in the 90's. I think a better option would be to leave your cooktop where it is and move your sink to the island.

There’s an inoperable window above it there too:/ I like the view facing into the rest of the house. We have 7 grown kids and at the island keeps the cook in the middle of the action as well as it has a good view of the fireplace ad 75” tv in the family room. Here’s the whole space

First, downdrafts are not very good hoods. If you do much more than boil water, then you need a real hood, especially since your Kitchen is so open to the rest of the home. About the only time downdrafts work at all is if the pots/pans are right up next to the raised fan -and- shorter than the top of the fan by a few inches.

That means no cooking on front or center burners. No using tall pots, even next to the downdraft. I used one for a couple of weeks in a rental and I hated it! It was noisy and did nothing to capture splattering grease. The range & downdraft were on a peninsula with a raised counter behind it. One of my kids was splattered with grease and I had ban my children from sitting at the counter when I was cooking. (Steam also billowed up from the front burner when I boiled water and the downdraft did absolutely nothing to capture it.)

While I don't generally like cooktops/ranges in islands or peninsulas, at least your island can handle it. You appear to have at least 24" on the outside side of the cooktop, 36" b/w the sink and cooktop, and at least 18" b/w the prep sink and other edge of the island. You also appear to have at least 24" b/w the back of the cooktop and the seating overhang behind it. Personally, I'd want more than 36" of prep space, but that is the minimum recommended prep space.

However, I see other issues. Are you and your family quite short? I'm asking b/c wall ovens mounted under the counter are much lower to the floor than ovens in a range. Unless you are quite short, I strongly advise against an under counter wall oven. Ditto an under counter MW, unless it's a MW drawer. I advise you to go somewhere where they're installed and try to spend time pretending to use them. Think about taking a 20-pound turkey + stuffing + pan out of such a low oven.

Another issue is that the island is a "barrier island". It's a barrier b/w the Prep Zone & refrigerator and b/w the Cooking Zone & refrigerator.

We have a 30 inch cooktop with a telescoping down draft in our island and it is not my favorite. The cooktop gets in the way of having work space for prepping food and then the downdraft is temperamental. When you do use it, it is in the middle of the kitchen and you are walking around a loud noise.

FYI...the DW door will extend approx 27" from the DW body. You probably won't be able to use any drawers or cabinets within 27" of the corner when the DW is open.

Yes, most of us are short (ladies 4’11- 5’2” and guys 5’ 9” and under. In fact we are dropping the island to 33/34”. I also have mobility issues so the ovens will have swing open doors. The members of our household have developed some great strategies to get things done and enjoy our time in the kitchen. I recognize those strategies are not at all efficient for the general population. What would be the most innocuous venting option for a mid-century modern with tongue and groove ceiling?

The ceiling is about 10’6” high over the proposed cooktop.

That layout needs a big rethink. Don’t add dysfunction.

Please elaborate