I think it's fine for the sink not to be centered on the cooktop. No one sees the view from the top. Ask your designer for a perspective view from the far side of the island so you can see what it will look like (after he/she adds countertops to the drawing).

What is the plan for the 2 - 15" cabinets on each side of the cooktop? Are they pullouts? They aren't wide enough to be great storage if there are shelves inside.

I also like tray dividers above the refrig in a space that lends itself to storage of cookie sheets, platters, cutting boards, etc.

It’s the jig jog up and down that is imbalanced. Pick one height, and stick to it. The hood is too high unless the rest are going to be stacked cabinets to reach that height.

If the sink is going to be off center, it should give you more space on the fridge end of the island where all of your prep will occur. The DW should be on the opposite side. Put the trash and drawer base on the fridge side, and just the DW and an end panel on the other.

I’m assuming you will have no overhang for seating because support for that isn’t designed into the island. And there is no pony wall to put the plumbing pipes in. They will all be in the sink cabinet, taking up all the space there.