I am nearing the end of a complete gut of our 1960 kitchen. I'm at the granite stage now.
Here are a few things to consider.
The cabinets look better if they do not go to the wall edge at an opening or door, leave 3" to 6"
Don't make the same mistake someone else did and put the cook top on the other side of the island from the sink.
We have induction and went with the built in oven in a separate cabinet.
Keep the walk between the sink, cook top and fridge as short as you can, with a prep area near the fridge so you can unload it.
Think about bumping up some cabinets and bumping out some to give depth to them. If you bump out any bottom cabinets you have to buy more granite, normally the granite is cut to 25" but if you bump out the sink cab. 3" you have to buy 28" wide for the length that the sink is in.
Molding around the top.
Consider the the placement of the lighting, ceiling, under and over cabinets.
Consider building in the fridge and door swing.
I would make a more grand entrance from the dining room. Maybe at the middle of the Island. 6ft wide.
Try to enjoy the ride. Don't consider divorce until finished.

I think maybe not knowing where you want stuff needs some study?

Perhaps enlist dh to watch how you actually cook? It can be useful to know what you DO versus what we all like to think we do. Zoning stuff is very personal and completely depends on how you cook or bake. It defines the relationships between the actions involved in cooking and the storage of stuff and food. Once you know that, you'll know where you want the appliances.

So below is a bit of what I thought when I saw your plan v. your description. Trying to figure out what might make this kitchen great for you by trying figuring out how you see yourself using this space, not judging in any way.

Which way do you want to face? I'd want to face the breakfast area windows and people. I'd try to face that direction or be edge onto that direction when I was at the cooktop and prepping. For me, its not important to face any given direction doing clean up because it doesn't take very long, but facing a certain direction might be important to you.

Where the dish storage is in relationship to when and where you need dishes might be important.

When you see buffets and guests using the space in your mind, where are the stools? Will you have to relocate them when you entertain in order to set up the buffet? How do buffet diners arrive at the buffet? Where do buffet diners sit? Are you sure you want to pull the stools out, duck under the island top with the overhang and open up cabinets? What kinda things would you keep under there?

Why is there an extra entrance from the living room?

What do you see when you look out the window over the sink? A wall of another part of the house? Is there an opportunity vista by sliding the window south a bit so a person in the hallway can see out?

Where's the bar? If thinking about entertaining and buffets, do you make a seperate dessert display? Where's coffee? Where's wine service? Are guests constantly diving into the ref for drinks?

How much stuff do you have and where do you use it? That's an army of cabinets and countertop, but might also be a lot of running around.

What do you want in the breakfast area? (If I had one, it would have two wing chairs and a round breakfast table. Maybe some shelves and a foot stool, maybe a sofa, maybe a drop front bill paying desk. Dang, I'd have to rent a puppy too!)

Thanks for the advice so far. Bmorepanic, you've given me some things to think about. When I have a few more minutes, I'm going to go through and answer all of your questions. I realize there were a few things I also didn't make clear in the original post.

I do have an idea about the appliances, so I'll re-do the plan and post the appliances where I was considering them.

It's sort of hard for me to plan this kithcen, because it's what I consider my first "real" kitchen. I'm 24 years old and just out of law school, studying for the bar. Until this point, I've basically used dorm room/apartment kitchens, and the kitchen of the home we live in know is nothing to write home about. I've always considered it temporary. I have about 4 feet of usuable counter space, and 3 useful cabinets. For these reasons, it's really hard to imagine how'd I'd use a larger space. I'm hoping some of the more experienced kitchen users on the forum can help with ideas.