Here is my latest update with a little help from the KD. We decided to just meet her and if we didn't think we would work well together just not use her. She ended up being very knowledgeable and easy to work with. Here is where we are with our idea.

We are thinking of taking off the wall of cabinets on the DR wall and making that a half-wall with a wooden countertop/seating area instead. With wainscoat below and around the DR. Then looking at adding other DR storage down the road instead of just extending our kitchen cabinets into there.

I could never have a cleanup sink on a 24" deep island with no wall or extended counter behind. With the water that gets behind the faucet and the splashes on my window, I can only imagine how messy and slippery the traffic path behind that sink will be!

These seems quite long and spread out. You might have room for a deeper island in the center of things, because your aisle in front of the stove seems, perhaps, roomier than you might need. I'd prefer to have the cleanup area at the end (hopefully with some dish storage room, which I really don't see anywhere), and use a slightly deeper island for prep across from the stove. I'd then end the island with the stove run or maybe the snack area, and not have it extend oddly in front of the window seat.

OR
I might want to swap the left sink and stove, to tighten the work area, and further separate the cooking and cleanup zones, still using a deeper island for prep. Still shortening the island.

I would want to do a 90-degree front corner cabinet instead of the diagonal front base cabinet that is shown, because it intrudes on your floor space and creates an unnecessarily deep corner. With the 90-degree front, you get a wider opening to access the interior, and longer runs of cabinet edge on both adjacent runs. Plus, you'll be able to reach the wall cabinet better.