Thank you to everyone who provided such helpful advice when I posted our original layout for our kitchen reno. I've now updated our layout based on all the terrific suggestions:

We've decided to go with a 48" Miele dual-fuel range (with convection oven + speed oven; 6 gas burners + griddle); removing the wall ovens has allowed us to free up space along the fridge wall to fit in a walk-in pantry, which we think will be a huge benefit in this space (hide many of our countertop appliances, along with providing out-of-sight but easily accessible storage for a small countertop microwave and all my baking tools & supplies).

We've also added a shallow reach-in pantry on the other side of the island, which we'll use as our food pantry.

We've added a prep sink, as suggested (and I think we'll add a single dishwasher drawer in the island, in addition to our standard dishwasher along the perimeter).

The overall layout of the design seems like it will work well for the way we use our kitchen. I've also compiled an inventory of everything in our kitchen and have virtually "put away" everything into the cabinets and pantries, so I think we now have plenty of storage where we need it for each zone.

Note that my drawing may not be precisely to scale (I'm not living in our house right now, so can't take my own measurements and we're working with a designer who is perfect for our project for a variety of other reasons, but she's not a great kitchen designer -- nor is she a cook/baker and I am both --, so I've based my drawing on the initial drawings from her and have then played around with it in Illustrator, as I'm a graphic designer and that's what I know). So some measurements may be a tiny bit off. Once we are happy with our layout, our designer will have proper drawings done based on exact measurements.

Regarding windows: the main perimeter wall in the kitchen is the side wall of our house and is only about 5' away from our neighbours' side wall, which is a massive wall of brick, so we have no view along that wall. Our current plan is to close of the two large existing windows to allow for this new layout, but to add back a small window about the clean-up sink to make it feel more open above the sink (although not a great view, but we'll address that with the glass or window treatments somehow). We get a TON of natural light that floods in from the back of the house (right side of my drawing, which faces south-west), through the double french doors and the new huge picture window we're adding, so I'm not too concerned about the kitchen's light situation -- I think (I hope!) we'll have lots of natural light, even with removing the two existing windows (which currently don't provide a ton of natural light, despite their size).

I'd appreciate any further advice/suggestions from all of you who are so experienced in this area, before we go ahead and finalize this layout, in case there is anything further we haven't thought of for improving the function of this space. It's starting to feel like a much better plan!

Thank you so much!!