my two cents...
I don't think you need another sink unless you want to put your wash sink on the wall and a prep sink in the island. islands are great spaces to prep, and would be the best place to prep in your kitchen. if you are not the type of person who washes and dries dishes immediately, your island will not be your prep space because it will be full of dirty and/or drying dishes. not judging at all if this is you, because that's exactly the situation in my kitchen.
If this was my kitchen I'd put the fridge and freezer together on the range wall, put a wash sink on the fridge wall, and put a prep sink in the island.

specifically, put your fridge at the dining room end of your range wall so it's easily accessible and not in the cooking zone. microwave can go in the island acrid from the fridge. put your dishwasher next to your wash sink, wherever that ends up being.

Similar to above, but If you stick with the same general plan, maybe reverse the fridge and freezer. You’re more likely access the freezer while cooking than someone in the living or dining room & fridge traffic can stay away from your cooking zone.

I personally don’t like the placement of a refrigerator at a doorway. If someone is standing at the fridge with the door open, you can’t easily walk in or out the mudroom.

I can't find mention of a pantry. If no other space is dedicated to a pantry, and even if it is, I'd move the fridge down, to include a full-height cabinet between it and the entry. If not needed for food storage, it could be an extension of mudroom storage, broom cabinet, etc.

I would put a second sink on that run, and make a coffee/snack center, which could be used as a second prep space if helpers are available. The UC fridge could be moved to that run, if feasible. I drew two options for the MW--in an upper beside the fridge, or a drawer on the island, facing the fridge.

Switch the DW to the left of the sink, and store dishes across the aisle, where it will be convenient for helpers to unload DW, or gather dishes to set the table, without entering the prep and cooking triangle. I will probably take some heat for centering the sink on the range, but you'll be spending more prepping to the side, than rinsing items in the sink, so you need the wider space there, and that side will be a nice drop zone for groceries to be loaded to the fridge and tall pantry.

I added an extra seat to the end of the island, which is better for conversation than all seats in a row. You actually have the depth to make the island 48" deep, for two seats on the end.

Deeper island with two seats on short end:

Option with three seats on the long side:

BTW, the NKBA recommends 15" minimum for seating overhang at counter height, and 24" elbow space for each seat. An island with a 1" front overhang, 24" deep cabinets, back panel (1/4" to 3/4"?), and 15" seating overhang would be 41-42" deep. Steel bar support system, legs and apron, or corbels, will be needed, especially for the wider overhang.

If no one else has mentioned it already, I'd suggest drawer bases wherever possible, rather than drawer and door cabinets.

Based on your plan, it looks like you have an undercounter fridge in an adjacent area. Butler's pantry? Bar? I'd consider putting a bar sink in the same area as the undercounter fridge. Agree there's really no need for a prep sink in the current kitchen layout.

I was going to suggest putting the fridge where "freezer" is marked on your plan, but that does have the disadvantage that it's a lot of walking while making meals. mama goose's plan is pretty great, in that it puts everything where it's handy. I was going to suggest a coffee/beverage station on that wall, which she has included, and it makes more sense to me to put snack stuff there too (out of the cooking zone) than in the other room.