I would put the sink and dishwasher where the window seat is and more work top along there up to the tall unit.
The hob would go inbetween the windows and the ovens would be stacked to have a pullout or swing out larder cupboard beside them. I'd use that larder for spices and cooking ingredients, as near the hob and ovens.
The appliance/breakfast unit would be flush and normal sized (not a narrower cupboard) and I would have slide and hide doors on this, to be used for appliances, hot drinks prep and breakfast but gaining the full width of the unit.
Your snug area is great and so is the dining room and circulation space.
I would not have bi folds, so many are coming to the end of their life and its not ten or 15 years, in many cases its 6 or 8 years. They are overpriced as they are so popular especially when French doors and sliding doors, look just as good.
I would have nothing but sockets on the island. I would have normal sockets on each side as lots of people report the pop up ones failing over time and food and gunk getting caught in them, that probably contributes to their failure. Sockets comes in great metal finishes and colours and marble, glass etc.
The only other thing is more drawers, you may regret not having more.